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Angles between vectors of center of two incircles


Relationship between circles touching incircleCan the angles be found?Angle Between Two TangentsHow to computer two Euler Angles between two vectorsUsing overlap area to determine distance between overlapping circlesSolve for quadrilateral with minimal difference between interior anglesFind the angles between two solidsWhy is the angle between vectors restricted?Shortest distance between two rectangles in 2D






.everyoneloves__top-leaderboard:empty,.everyoneloves__mid-leaderboard:empty,.everyoneloves__bot-mid-leaderboard:empty margin-bottom:0;








2












$begingroup$


I have two two incircle between rectangle and two
quadrilateral circlein. It's possible to determine exact value of $phi,$ angles between vectors of center of two circles.



enter image description here










share|cite|improve this question









$endgroup$




















    2












    $begingroup$


    I have two two incircle between rectangle and two
    quadrilateral circlein. It's possible to determine exact value of $phi,$ angles between vectors of center of two circles.



    enter image description here










    share|cite|improve this question









    $endgroup$
















      2












      2








      2


      3



      $begingroup$


      I have two two incircle between rectangle and two
      quadrilateral circlein. It's possible to determine exact value of $phi,$ angles between vectors of center of two circles.



      enter image description here










      share|cite|improve this question









      $endgroup$




      I have two two incircle between rectangle and two
      quadrilateral circlein. It's possible to determine exact value of $phi,$ angles between vectors of center of two circles.



      enter image description here







      geometry circles angle rectangles






      share|cite|improve this question













      share|cite|improve this question











      share|cite|improve this question




      share|cite|improve this question










      asked 11 hours ago









      BarzanHayatiBarzanHayati

      4542 silver badges12 bronze badges




      4542 silver badges12 bronze badges























          4 Answers
          4






          active

          oldest

          votes


















          4












          $begingroup$

          Place the origin $O$ at the lower left-hand corner, and let the positive $x,y$-axes be the the natural choices based on the diagram.



          Let $r$ be the radius of the red circle.



          Let $P,Q$ be the centers of the circles of radii $2,1$, respectively.



          Then we can express the coordinates of $P,Q$ as $P=(x,2)$ and $Q=(x,r-1)$, where $x$ is an unknown.



          Computing $|OQ|$ in two ways, we get the equation
          $$sqrtx^2+(r-1)^2=r+1$$
          hence
          $$x^2+(r-1)^2=(r+1)^2tageq1$$
          Computing $|OP|$ in two ways, we get the equation
          $$sqrtx^2+2^2=r-2$$
          hence
          $$x^2+4=(r-2)^2tageq2$$
          From $(texteq1),-,(texteq2)$, we get $r=8$.



          Plugging $r=8$ into $(texteq2)$, we get $x=4sqrt2$.



          Using the known values of $r$ and $x$, the distance formula yields
          beginalign*
          |OP|&=6\[4pt]
          |OQ|&=9\[4pt]
          |PQ|&=5\[4pt]
          endalign*

          hence by the law of cosines, $cos(largephi)=largefrac2327$, so we get $largephi=cos^-1bigl(largefrac2327bigr)$.






          share|cite|improve this answer









          $endgroup$














          • $begingroup$
            that's slick!..
            $endgroup$
            – ganeshie8
            10 hours ago


















          2












          $begingroup$

          Using Pythagoras theorem is not difficult to find that the radius $B$ of red arcs is $8$. It follows that $PQ=6$, $PR=9$ and $QR=5$. Apply now the cosine rule to triangle $PQR$ to find
          $$
          cosphi=23over27.
          $$



          enter image description here






          share|cite|improve this answer









          $endgroup$






















            1












            $begingroup$

            enter image description here



            Let $|AB|=|CD|=a$,$|BC|=|AD|=b$,
            $|O_1E|=r_1$,
            $|O_2F|=r_2$,
            $angle O_1AO_2=phi$,
            $angle O_1AF=alpha$
            $angle O_2AF=beta$.



            Then
            beginalign
            tanalpha&=fracb-r_1a/2
            tag1label1
            ,\
            sinalpha&=fracb-r_1b+r_1
            ,\
            tanalpha&=fracsinalphasqrt1-sin^2alpha
            =fracb-r_1b+r_1
            left/
            sqrt1-Big( fracb-r_1b+r_1 Big)^2 right.
            =tfrac12,fracb-r_1sqrtb,r_1
            tag2label2
            .
            endalign



            From eqref1$=$eqref2 it follows
            beginalign
            a&=4,sqrtb,r_1
            tag3label3
            .
            endalign



            Similarly,
            beginalign
            tanbeta&=frac2r_2a
            tag4label4
            ,\
            sinbeta&=fracr_2b-r_2
            ,\
            tanbeta&=
            fracsinbetasqrt1-sin^2beta
            =fracr_2sqrtb,(b-2,r_2)
            tag5label5
            .
            endalign



            From eqref4$=$eqref5:
            beginalign
            a&=2,sqrtb,(b-2,r_2)
            tag6label6
            ,
            endalign



            and from eqref3$=$eqref6
            we have



            beginalign
            b&=4r_1+2r_2
            ,\
            a&=4,sqrtr_1,(4,r_1+2,r_2)
            .
            endalign



            beginalign
            tanphi&=tan(alpha-beta)
            =fractanalpha-tanbeta1+tanalphatanbeta
            =frac2(3r_1+r_2),sqrt2,r_1,(2,r_1+r_2)16,r_1^2+11,r_1,r_2+2,r_2^2
            endalign



            For $r_1=1$, $r_2=2$ we have



            beginalign
            a&=8,sqrt2approx 11.31370850
            ,\
            b&=8
            ,\
            phi&=arctanBig(frac10,sqrt223 Big)
            approx 31.586338^circ
            .
            endalign






            share|cite|improve this answer









            $endgroup$






















              0












              $begingroup$

              There are constraints that $A$ and $B$ must fullfil, i.e., the following system of equations coming from Pythagoras theorem applied to certain right triangles :



              $$begincases(B-2)^2+2^2=(A/2)^2\(B-1)^2+(A/2)^2=(B+1)^2endcases$$



              giving $A=8 sqrt2$ and $B=8$.



              If now we take equations as in the partial solution you gave (a good idea) :



              $$tan(theta) = dfrac2A/2 = dfracsqrt24tag1$$



              and



              $$tan(phi + theta) = dfrac74 sqrt2tag2$$



              Equation (2) can also be written :



              $$dfractan(phi) + tan(theta)1-tan(phi)tan(theta) = dfrac7sqrt28tag3$$



              from which we can extract the numerical value of $tan(phi)$. Up to you...






              share|cite|improve this answer











              $endgroup$














              • $begingroup$
                It would be great if you add your answer.
                $endgroup$
                – BarzanHayati
                10 hours ago










              • $begingroup$
                I am going to write it.
                $endgroup$
                – Jean Marie
                9 hours ago













              Your Answer








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              4 Answers
              4






              active

              oldest

              votes








              4 Answers
              4






              active

              oldest

              votes









              active

              oldest

              votes






              active

              oldest

              votes









              4












              $begingroup$

              Place the origin $O$ at the lower left-hand corner, and let the positive $x,y$-axes be the the natural choices based on the diagram.



              Let $r$ be the radius of the red circle.



              Let $P,Q$ be the centers of the circles of radii $2,1$, respectively.



              Then we can express the coordinates of $P,Q$ as $P=(x,2)$ and $Q=(x,r-1)$, where $x$ is an unknown.



              Computing $|OQ|$ in two ways, we get the equation
              $$sqrtx^2+(r-1)^2=r+1$$
              hence
              $$x^2+(r-1)^2=(r+1)^2tageq1$$
              Computing $|OP|$ in two ways, we get the equation
              $$sqrtx^2+2^2=r-2$$
              hence
              $$x^2+4=(r-2)^2tageq2$$
              From $(texteq1),-,(texteq2)$, we get $r=8$.



              Plugging $r=8$ into $(texteq2)$, we get $x=4sqrt2$.



              Using the known values of $r$ and $x$, the distance formula yields
              beginalign*
              |OP|&=6\[4pt]
              |OQ|&=9\[4pt]
              |PQ|&=5\[4pt]
              endalign*

              hence by the law of cosines, $cos(largephi)=largefrac2327$, so we get $largephi=cos^-1bigl(largefrac2327bigr)$.






              share|cite|improve this answer









              $endgroup$














              • $begingroup$
                that's slick!..
                $endgroup$
                – ganeshie8
                10 hours ago















              4












              $begingroup$

              Place the origin $O$ at the lower left-hand corner, and let the positive $x,y$-axes be the the natural choices based on the diagram.



              Let $r$ be the radius of the red circle.



              Let $P,Q$ be the centers of the circles of radii $2,1$, respectively.



              Then we can express the coordinates of $P,Q$ as $P=(x,2)$ and $Q=(x,r-1)$, where $x$ is an unknown.



              Computing $|OQ|$ in two ways, we get the equation
              $$sqrtx^2+(r-1)^2=r+1$$
              hence
              $$x^2+(r-1)^2=(r+1)^2tageq1$$
              Computing $|OP|$ in two ways, we get the equation
              $$sqrtx^2+2^2=r-2$$
              hence
              $$x^2+4=(r-2)^2tageq2$$
              From $(texteq1),-,(texteq2)$, we get $r=8$.



              Plugging $r=8$ into $(texteq2)$, we get $x=4sqrt2$.



              Using the known values of $r$ and $x$, the distance formula yields
              beginalign*
              |OP|&=6\[4pt]
              |OQ|&=9\[4pt]
              |PQ|&=5\[4pt]
              endalign*

              hence by the law of cosines, $cos(largephi)=largefrac2327$, so we get $largephi=cos^-1bigl(largefrac2327bigr)$.






              share|cite|improve this answer









              $endgroup$














              • $begingroup$
                that's slick!..
                $endgroup$
                – ganeshie8
                10 hours ago













              4












              4








              4





              $begingroup$

              Place the origin $O$ at the lower left-hand corner, and let the positive $x,y$-axes be the the natural choices based on the diagram.



              Let $r$ be the radius of the red circle.



              Let $P,Q$ be the centers of the circles of radii $2,1$, respectively.



              Then we can express the coordinates of $P,Q$ as $P=(x,2)$ and $Q=(x,r-1)$, where $x$ is an unknown.



              Computing $|OQ|$ in two ways, we get the equation
              $$sqrtx^2+(r-1)^2=r+1$$
              hence
              $$x^2+(r-1)^2=(r+1)^2tageq1$$
              Computing $|OP|$ in two ways, we get the equation
              $$sqrtx^2+2^2=r-2$$
              hence
              $$x^2+4=(r-2)^2tageq2$$
              From $(texteq1),-,(texteq2)$, we get $r=8$.



              Plugging $r=8$ into $(texteq2)$, we get $x=4sqrt2$.



              Using the known values of $r$ and $x$, the distance formula yields
              beginalign*
              |OP|&=6\[4pt]
              |OQ|&=9\[4pt]
              |PQ|&=5\[4pt]
              endalign*

              hence by the law of cosines, $cos(largephi)=largefrac2327$, so we get $largephi=cos^-1bigl(largefrac2327bigr)$.






              share|cite|improve this answer









              $endgroup$



              Place the origin $O$ at the lower left-hand corner, and let the positive $x,y$-axes be the the natural choices based on the diagram.



              Let $r$ be the radius of the red circle.



              Let $P,Q$ be the centers of the circles of radii $2,1$, respectively.



              Then we can express the coordinates of $P,Q$ as $P=(x,2)$ and $Q=(x,r-1)$, where $x$ is an unknown.



              Computing $|OQ|$ in two ways, we get the equation
              $$sqrtx^2+(r-1)^2=r+1$$
              hence
              $$x^2+(r-1)^2=(r+1)^2tageq1$$
              Computing $|OP|$ in two ways, we get the equation
              $$sqrtx^2+2^2=r-2$$
              hence
              $$x^2+4=(r-2)^2tageq2$$
              From $(texteq1),-,(texteq2)$, we get $r=8$.



              Plugging $r=8$ into $(texteq2)$, we get $x=4sqrt2$.



              Using the known values of $r$ and $x$, the distance formula yields
              beginalign*
              |OP|&=6\[4pt]
              |OQ|&=9\[4pt]
              |PQ|&=5\[4pt]
              endalign*

              hence by the law of cosines, $cos(largephi)=largefrac2327$, so we get $largephi=cos^-1bigl(largefrac2327bigr)$.







              share|cite|improve this answer












              share|cite|improve this answer



              share|cite|improve this answer










              answered 10 hours ago









              quasiquasi

              40.3k3 gold badges29 silver badges71 bronze badges




              40.3k3 gold badges29 silver badges71 bronze badges














              • $begingroup$
                that's slick!..
                $endgroup$
                – ganeshie8
                10 hours ago
















              • $begingroup$
                that's slick!..
                $endgroup$
                – ganeshie8
                10 hours ago















              $begingroup$
              that's slick!..
              $endgroup$
              – ganeshie8
              10 hours ago




              $begingroup$
              that's slick!..
              $endgroup$
              – ganeshie8
              10 hours ago













              2












              $begingroup$

              Using Pythagoras theorem is not difficult to find that the radius $B$ of red arcs is $8$. It follows that $PQ=6$, $PR=9$ and $QR=5$. Apply now the cosine rule to triangle $PQR$ to find
              $$
              cosphi=23over27.
              $$



              enter image description here






              share|cite|improve this answer









              $endgroup$



















                2












                $begingroup$

                Using Pythagoras theorem is not difficult to find that the radius $B$ of red arcs is $8$. It follows that $PQ=6$, $PR=9$ and $QR=5$. Apply now the cosine rule to triangle $PQR$ to find
                $$
                cosphi=23over27.
                $$



                enter image description here






                share|cite|improve this answer









                $endgroup$

















                  2












                  2








                  2





                  $begingroup$

                  Using Pythagoras theorem is not difficult to find that the radius $B$ of red arcs is $8$. It follows that $PQ=6$, $PR=9$ and $QR=5$. Apply now the cosine rule to triangle $PQR$ to find
                  $$
                  cosphi=23over27.
                  $$



                  enter image description here






                  share|cite|improve this answer









                  $endgroup$



                  Using Pythagoras theorem is not difficult to find that the radius $B$ of red arcs is $8$. It follows that $PQ=6$, $PR=9$ and $QR=5$. Apply now the cosine rule to triangle $PQR$ to find
                  $$
                  cosphi=23over27.
                  $$



                  enter image description here







                  share|cite|improve this answer












                  share|cite|improve this answer



                  share|cite|improve this answer










                  answered 10 hours ago









                  AretinoAretino

                  27.4k3 gold badges20 silver badges48 bronze badges




                  27.4k3 gold badges20 silver badges48 bronze badges
























                      1












                      $begingroup$

                      enter image description here



                      Let $|AB|=|CD|=a$,$|BC|=|AD|=b$,
                      $|O_1E|=r_1$,
                      $|O_2F|=r_2$,
                      $angle O_1AO_2=phi$,
                      $angle O_1AF=alpha$
                      $angle O_2AF=beta$.



                      Then
                      beginalign
                      tanalpha&=fracb-r_1a/2
                      tag1label1
                      ,\
                      sinalpha&=fracb-r_1b+r_1
                      ,\
                      tanalpha&=fracsinalphasqrt1-sin^2alpha
                      =fracb-r_1b+r_1
                      left/
                      sqrt1-Big( fracb-r_1b+r_1 Big)^2 right.
                      =tfrac12,fracb-r_1sqrtb,r_1
                      tag2label2
                      .
                      endalign



                      From eqref1$=$eqref2 it follows
                      beginalign
                      a&=4,sqrtb,r_1
                      tag3label3
                      .
                      endalign



                      Similarly,
                      beginalign
                      tanbeta&=frac2r_2a
                      tag4label4
                      ,\
                      sinbeta&=fracr_2b-r_2
                      ,\
                      tanbeta&=
                      fracsinbetasqrt1-sin^2beta
                      =fracr_2sqrtb,(b-2,r_2)
                      tag5label5
                      .
                      endalign



                      From eqref4$=$eqref5:
                      beginalign
                      a&=2,sqrtb,(b-2,r_2)
                      tag6label6
                      ,
                      endalign



                      and from eqref3$=$eqref6
                      we have



                      beginalign
                      b&=4r_1+2r_2
                      ,\
                      a&=4,sqrtr_1,(4,r_1+2,r_2)
                      .
                      endalign



                      beginalign
                      tanphi&=tan(alpha-beta)
                      =fractanalpha-tanbeta1+tanalphatanbeta
                      =frac2(3r_1+r_2),sqrt2,r_1,(2,r_1+r_2)16,r_1^2+11,r_1,r_2+2,r_2^2
                      endalign



                      For $r_1=1$, $r_2=2$ we have



                      beginalign
                      a&=8,sqrt2approx 11.31370850
                      ,\
                      b&=8
                      ,\
                      phi&=arctanBig(frac10,sqrt223 Big)
                      approx 31.586338^circ
                      .
                      endalign






                      share|cite|improve this answer









                      $endgroup$



















                        1












                        $begingroup$

                        enter image description here



                        Let $|AB|=|CD|=a$,$|BC|=|AD|=b$,
                        $|O_1E|=r_1$,
                        $|O_2F|=r_2$,
                        $angle O_1AO_2=phi$,
                        $angle O_1AF=alpha$
                        $angle O_2AF=beta$.



                        Then
                        beginalign
                        tanalpha&=fracb-r_1a/2
                        tag1label1
                        ,\
                        sinalpha&=fracb-r_1b+r_1
                        ,\
                        tanalpha&=fracsinalphasqrt1-sin^2alpha
                        =fracb-r_1b+r_1
                        left/
                        sqrt1-Big( fracb-r_1b+r_1 Big)^2 right.
                        =tfrac12,fracb-r_1sqrtb,r_1
                        tag2label2
                        .
                        endalign



                        From eqref1$=$eqref2 it follows
                        beginalign
                        a&=4,sqrtb,r_1
                        tag3label3
                        .
                        endalign



                        Similarly,
                        beginalign
                        tanbeta&=frac2r_2a
                        tag4label4
                        ,\
                        sinbeta&=fracr_2b-r_2
                        ,\
                        tanbeta&=
                        fracsinbetasqrt1-sin^2beta
                        =fracr_2sqrtb,(b-2,r_2)
                        tag5label5
                        .
                        endalign



                        From eqref4$=$eqref5:
                        beginalign
                        a&=2,sqrtb,(b-2,r_2)
                        tag6label6
                        ,
                        endalign



                        and from eqref3$=$eqref6
                        we have



                        beginalign
                        b&=4r_1+2r_2
                        ,\
                        a&=4,sqrtr_1,(4,r_1+2,r_2)
                        .
                        endalign



                        beginalign
                        tanphi&=tan(alpha-beta)
                        =fractanalpha-tanbeta1+tanalphatanbeta
                        =frac2(3r_1+r_2),sqrt2,r_1,(2,r_1+r_2)16,r_1^2+11,r_1,r_2+2,r_2^2
                        endalign



                        For $r_1=1$, $r_2=2$ we have



                        beginalign
                        a&=8,sqrt2approx 11.31370850
                        ,\
                        b&=8
                        ,\
                        phi&=arctanBig(frac10,sqrt223 Big)
                        approx 31.586338^circ
                        .
                        endalign






                        share|cite|improve this answer









                        $endgroup$

















                          1












                          1








                          1





                          $begingroup$

                          enter image description here



                          Let $|AB|=|CD|=a$,$|BC|=|AD|=b$,
                          $|O_1E|=r_1$,
                          $|O_2F|=r_2$,
                          $angle O_1AO_2=phi$,
                          $angle O_1AF=alpha$
                          $angle O_2AF=beta$.



                          Then
                          beginalign
                          tanalpha&=fracb-r_1a/2
                          tag1label1
                          ,\
                          sinalpha&=fracb-r_1b+r_1
                          ,\
                          tanalpha&=fracsinalphasqrt1-sin^2alpha
                          =fracb-r_1b+r_1
                          left/
                          sqrt1-Big( fracb-r_1b+r_1 Big)^2 right.
                          =tfrac12,fracb-r_1sqrtb,r_1
                          tag2label2
                          .
                          endalign



                          From eqref1$=$eqref2 it follows
                          beginalign
                          a&=4,sqrtb,r_1
                          tag3label3
                          .
                          endalign



                          Similarly,
                          beginalign
                          tanbeta&=frac2r_2a
                          tag4label4
                          ,\
                          sinbeta&=fracr_2b-r_2
                          ,\
                          tanbeta&=
                          fracsinbetasqrt1-sin^2beta
                          =fracr_2sqrtb,(b-2,r_2)
                          tag5label5
                          .
                          endalign



                          From eqref4$=$eqref5:
                          beginalign
                          a&=2,sqrtb,(b-2,r_2)
                          tag6label6
                          ,
                          endalign



                          and from eqref3$=$eqref6
                          we have



                          beginalign
                          b&=4r_1+2r_2
                          ,\
                          a&=4,sqrtr_1,(4,r_1+2,r_2)
                          .
                          endalign



                          beginalign
                          tanphi&=tan(alpha-beta)
                          =fractanalpha-tanbeta1+tanalphatanbeta
                          =frac2(3r_1+r_2),sqrt2,r_1,(2,r_1+r_2)16,r_1^2+11,r_1,r_2+2,r_2^2
                          endalign



                          For $r_1=1$, $r_2=2$ we have



                          beginalign
                          a&=8,sqrt2approx 11.31370850
                          ,\
                          b&=8
                          ,\
                          phi&=arctanBig(frac10,sqrt223 Big)
                          approx 31.586338^circ
                          .
                          endalign






                          share|cite|improve this answer









                          $endgroup$



                          enter image description here



                          Let $|AB|=|CD|=a$,$|BC|=|AD|=b$,
                          $|O_1E|=r_1$,
                          $|O_2F|=r_2$,
                          $angle O_1AO_2=phi$,
                          $angle O_1AF=alpha$
                          $angle O_2AF=beta$.



                          Then
                          beginalign
                          tanalpha&=fracb-r_1a/2
                          tag1label1
                          ,\
                          sinalpha&=fracb-r_1b+r_1
                          ,\
                          tanalpha&=fracsinalphasqrt1-sin^2alpha
                          =fracb-r_1b+r_1
                          left/
                          sqrt1-Big( fracb-r_1b+r_1 Big)^2 right.
                          =tfrac12,fracb-r_1sqrtb,r_1
                          tag2label2
                          .
                          endalign



                          From eqref1$=$eqref2 it follows
                          beginalign
                          a&=4,sqrtb,r_1
                          tag3label3
                          .
                          endalign



                          Similarly,
                          beginalign
                          tanbeta&=frac2r_2a
                          tag4label4
                          ,\
                          sinbeta&=fracr_2b-r_2
                          ,\
                          tanbeta&=
                          fracsinbetasqrt1-sin^2beta
                          =fracr_2sqrtb,(b-2,r_2)
                          tag5label5
                          .
                          endalign



                          From eqref4$=$eqref5:
                          beginalign
                          a&=2,sqrtb,(b-2,r_2)
                          tag6label6
                          ,
                          endalign



                          and from eqref3$=$eqref6
                          we have



                          beginalign
                          b&=4r_1+2r_2
                          ,\
                          a&=4,sqrtr_1,(4,r_1+2,r_2)
                          .
                          endalign



                          beginalign
                          tanphi&=tan(alpha-beta)
                          =fractanalpha-tanbeta1+tanalphatanbeta
                          =frac2(3r_1+r_2),sqrt2,r_1,(2,r_1+r_2)16,r_1^2+11,r_1,r_2+2,r_2^2
                          endalign



                          For $r_1=1$, $r_2=2$ we have



                          beginalign
                          a&=8,sqrt2approx 11.31370850
                          ,\
                          b&=8
                          ,\
                          phi&=arctanBig(frac10,sqrt223 Big)
                          approx 31.586338^circ
                          .
                          endalign







                          share|cite|improve this answer












                          share|cite|improve this answer



                          share|cite|improve this answer










                          answered 53 mins ago









                          g.kovg.kov

                          6,8111 gold badge8 silver badges23 bronze badges




                          6,8111 gold badge8 silver badges23 bronze badges
























                              0












                              $begingroup$

                              There are constraints that $A$ and $B$ must fullfil, i.e., the following system of equations coming from Pythagoras theorem applied to certain right triangles :



                              $$begincases(B-2)^2+2^2=(A/2)^2\(B-1)^2+(A/2)^2=(B+1)^2endcases$$



                              giving $A=8 sqrt2$ and $B=8$.



                              If now we take equations as in the partial solution you gave (a good idea) :



                              $$tan(theta) = dfrac2A/2 = dfracsqrt24tag1$$



                              and



                              $$tan(phi + theta) = dfrac74 sqrt2tag2$$



                              Equation (2) can also be written :



                              $$dfractan(phi) + tan(theta)1-tan(phi)tan(theta) = dfrac7sqrt28tag3$$



                              from which we can extract the numerical value of $tan(phi)$. Up to you...






                              share|cite|improve this answer











                              $endgroup$














                              • $begingroup$
                                It would be great if you add your answer.
                                $endgroup$
                                – BarzanHayati
                                10 hours ago










                              • $begingroup$
                                I am going to write it.
                                $endgroup$
                                – Jean Marie
                                9 hours ago















                              0












                              $begingroup$

                              There are constraints that $A$ and $B$ must fullfil, i.e., the following system of equations coming from Pythagoras theorem applied to certain right triangles :



                              $$begincases(B-2)^2+2^2=(A/2)^2\(B-1)^2+(A/2)^2=(B+1)^2endcases$$



                              giving $A=8 sqrt2$ and $B=8$.



                              If now we take equations as in the partial solution you gave (a good idea) :



                              $$tan(theta) = dfrac2A/2 = dfracsqrt24tag1$$



                              and



                              $$tan(phi + theta) = dfrac74 sqrt2tag2$$



                              Equation (2) can also be written :



                              $$dfractan(phi) + tan(theta)1-tan(phi)tan(theta) = dfrac7sqrt28tag3$$



                              from which we can extract the numerical value of $tan(phi)$. Up to you...






                              share|cite|improve this answer











                              $endgroup$














                              • $begingroup$
                                It would be great if you add your answer.
                                $endgroup$
                                – BarzanHayati
                                10 hours ago










                              • $begingroup$
                                I am going to write it.
                                $endgroup$
                                – Jean Marie
                                9 hours ago













                              0












                              0








                              0





                              $begingroup$

                              There are constraints that $A$ and $B$ must fullfil, i.e., the following system of equations coming from Pythagoras theorem applied to certain right triangles :



                              $$begincases(B-2)^2+2^2=(A/2)^2\(B-1)^2+(A/2)^2=(B+1)^2endcases$$



                              giving $A=8 sqrt2$ and $B=8$.



                              If now we take equations as in the partial solution you gave (a good idea) :



                              $$tan(theta) = dfrac2A/2 = dfracsqrt24tag1$$



                              and



                              $$tan(phi + theta) = dfrac74 sqrt2tag2$$



                              Equation (2) can also be written :



                              $$dfractan(phi) + tan(theta)1-tan(phi)tan(theta) = dfrac7sqrt28tag3$$



                              from which we can extract the numerical value of $tan(phi)$. Up to you...






                              share|cite|improve this answer











                              $endgroup$



                              There are constraints that $A$ and $B$ must fullfil, i.e., the following system of equations coming from Pythagoras theorem applied to certain right triangles :



                              $$begincases(B-2)^2+2^2=(A/2)^2\(B-1)^2+(A/2)^2=(B+1)^2endcases$$



                              giving $A=8 sqrt2$ and $B=8$.



                              If now we take equations as in the partial solution you gave (a good idea) :



                              $$tan(theta) = dfrac2A/2 = dfracsqrt24tag1$$



                              and



                              $$tan(phi + theta) = dfrac74 sqrt2tag2$$



                              Equation (2) can also be written :



                              $$dfractan(phi) + tan(theta)1-tan(phi)tan(theta) = dfrac7sqrt28tag3$$



                              from which we can extract the numerical value of $tan(phi)$. Up to you...







                              share|cite|improve this answer














                              share|cite|improve this answer



                              share|cite|improve this answer








                              edited 8 hours ago

























                              answered 10 hours ago









                              Jean MarieJean Marie

                              34.5k4 gold badges26 silver badges60 bronze badges




                              34.5k4 gold badges26 silver badges60 bronze badges














                              • $begingroup$
                                It would be great if you add your answer.
                                $endgroup$
                                – BarzanHayati
                                10 hours ago










                              • $begingroup$
                                I am going to write it.
                                $endgroup$
                                – Jean Marie
                                9 hours ago
















                              • $begingroup$
                                It would be great if you add your answer.
                                $endgroup$
                                – BarzanHayati
                                10 hours ago










                              • $begingroup$
                                I am going to write it.
                                $endgroup$
                                – Jean Marie
                                9 hours ago















                              $begingroup$
                              It would be great if you add your answer.
                              $endgroup$
                              – BarzanHayati
                              10 hours ago




                              $begingroup$
                              It would be great if you add your answer.
                              $endgroup$
                              – BarzanHayati
                              10 hours ago












                              $begingroup$
                              I am going to write it.
                              $endgroup$
                              – Jean Marie
                              9 hours ago




                              $begingroup$
                              I am going to write it.
                              $endgroup$
                              – Jean Marie
                              9 hours ago

















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