Question about a degree 5 polynomial with no rational rootsPolynomial roots of degree 2I need help proving a statement about rational rootsFourth degree polynomial with rational coefficients and a real rootNumber of roots of a polynomial of non-integer degreeQuestion about rational roots of polynomialWays to find irrational roots of an n degree polynomialHow to find polynomial functions 3rd degree with no, one, two, three zeros(roots)?Solving 5th degree polynomial
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Question about a degree 5 polynomial with no rational roots
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Question about a degree 5 polynomial with no rational roots
Polynomial roots of degree 2I need help proving a statement about rational rootsFourth degree polynomial with rational coefficients and a real rootNumber of roots of a polynomial of non-integer degreeQuestion about rational roots of polynomialWays to find irrational roots of an n degree polynomialHow to find polynomial functions 3rd degree with no, one, two, three zeros(roots)?Solving 5th degree polynomial
.everyoneloves__top-leaderboard:empty,.everyoneloves__mid-leaderboard:empty,.everyoneloves__bot-mid-leaderboard:empty margin-bottom:0;
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Is it possible to find a 5th degree polynomial with no rational roots, and at least one irrational root?
Edit: the polynomial must only have rational coefficients
functions polynomials
$endgroup$
add a comment
|
$begingroup$
Is it possible to find a 5th degree polynomial with no rational roots, and at least one irrational root?
Edit: the polynomial must only have rational coefficients
functions polynomials
$endgroup$
4
$begingroup$
how about $(x-pi)^5$ or $(x-e)^5$ or $(x-sqrt2)^5$?
$endgroup$
– J. W. Tanner
11 hours ago
2
$begingroup$
Or even just $x^5-2$?
$endgroup$
– Lord Shark the Unknown
10 hours ago
add a comment
|
$begingroup$
Is it possible to find a 5th degree polynomial with no rational roots, and at least one irrational root?
Edit: the polynomial must only have rational coefficients
functions polynomials
$endgroup$
Is it possible to find a 5th degree polynomial with no rational roots, and at least one irrational root?
Edit: the polynomial must only have rational coefficients
functions polynomials
functions polynomials
edited 10 hours ago
Diba
asked 11 hours ago
DibaDiba
135 bronze badges
135 bronze badges
4
$begingroup$
how about $(x-pi)^5$ or $(x-e)^5$ or $(x-sqrt2)^5$?
$endgroup$
– J. W. Tanner
11 hours ago
2
$begingroup$
Or even just $x^5-2$?
$endgroup$
– Lord Shark the Unknown
10 hours ago
add a comment
|
4
$begingroup$
how about $(x-pi)^5$ or $(x-e)^5$ or $(x-sqrt2)^5$?
$endgroup$
– J. W. Tanner
11 hours ago
2
$begingroup$
Or even just $x^5-2$?
$endgroup$
– Lord Shark the Unknown
10 hours ago
4
4
$begingroup$
how about $(x-pi)^5$ or $(x-e)^5$ or $(x-sqrt2)^5$?
$endgroup$
– J. W. Tanner
11 hours ago
$begingroup$
how about $(x-pi)^5$ or $(x-e)^5$ or $(x-sqrt2)^5$?
$endgroup$
– J. W. Tanner
11 hours ago
2
2
$begingroup$
Or even just $x^5-2$?
$endgroup$
– Lord Shark the Unknown
10 hours ago
$begingroup$
Or even just $x^5-2$?
$endgroup$
– Lord Shark the Unknown
10 hours ago
add a comment
|
5 Answers
5
active
oldest
votes
$begingroup$
In fact we can even achieve this with a polynomial with rational coefficients: [Edit: After I wrote this answer, OP added the rationality of the coefficients as a condition.]
The Rational Root Theorem implies that $$x^5 - 2$$ has no rational roots, but since its degree is odd, it has at least one real---and hence irrational---root. (In fact, can replace $2$ here with any rational number that is not a perfect $5$th power of a rational number.)
$endgroup$
1
$begingroup$
in fact with integer coefficients
$endgroup$
– J. W. Tanner
10 hours ago
1
$begingroup$
Indeed! That said, we can always clear the denominators of any rational polynomial by multiplying by their $operatornamelcm$, and this operation preserves the roots. (But it's true that this example is a monic polynomial with integer coefficients.)
$endgroup$
– Travis
10 hours ago
add a comment
|
$begingroup$
That is pretty easy, if there are not other propertys required. Just consider a polynomial like:
$(x-sqrt2)^5$
$endgroup$
$begingroup$
That doesn't have rational coefficients.
$endgroup$
– fleablood
5 hours ago
$begingroup$
@fleablood OP added the requirement that the coefficients be rational a few minutes after this answer was posted.
$endgroup$
– Travis
3 hours ago
add a comment
|
$begingroup$
If $alpha$ is irrational, then the polynomial $(x-alpha)^5$ has degree $5$, and the only (repeated) root is irrational.
$endgroup$
2
$begingroup$
More generally, $(x-a_1)(x-a_2)(x-a_3)(x-a_4)(x-a_5)$ for any irrational $a_1, dots, a_5$.
$endgroup$
– 79037662
10 hours ago
$begingroup$
I realize now that I might have phrased the question badly- it is only considering polynomials with rational coefficients.
$endgroup$
– Diba
10 hours ago
1
$begingroup$
@DibaHeydary: In that case, see the answer by Travis
$endgroup$
– J. W. Tanner
10 hours ago
add a comment
|
$begingroup$
$$ x^5 + x^4 - 4 x^3 - 3 x^2 + 3 x + 1 $$
Five real irrational roots,
$$ 2 cos left( frac2k
pi11 right) $$
If you prefer the roots to be $cos( 2k pi /11),$ adjust the quintic to
$$ 32x^5 + 16x^4 - 32 x^3 - 12 x^2 + 6 x + 1 $$
gp-pari:
? x = cos( 2 * Pi / 11)
%1 = 0.8412535328311811688618116489
? f = 32 * x^5 + 16 * x^4 - 32 * x^3 - 12 * x^2 + 6 * x + 1
%2 = -1.009741959 E-28
?
? x = cos( 4 * Pi / 11)
%3 = 0.4154150130018864255292741493
? f = 32 * x^5 + 16 * x^4 - 32 * x^3 - 12 * x^2 + 6 * x + 1
%4 = -2.019483917 E-28
?
? x = cos( 6 * Pi / 11)
%5 = -0.1423148382732851404437926686
? f = 32 * x^5 + 16 * x^4 - 32 * x^3 - 12 * x^2 + 6 * x + 1
%6 = -7.57306469 E-29
?
? x = cos( 8 * Pi / 11)
%7 = -0.6548607339452850640569250725
? f = 32 * x^5 + 16 * x^4 - 32 * x^3 - 12 * x^2 + 6 * x + 1
%8 = 0.E-28
?
=============================
$endgroup$
$begingroup$
I'm confused, how did you connect polynomials to triginometry? Through something like taylor series?
$endgroup$
– vikarjramun
2 hours ago
add a comment
|
$begingroup$
Well, $sqrt[5]m$ is irrational if $m$ is an integer that isn't a perfect power of $5$.
And $sqrt[5]m$ is a solution to $x^5 -m =0$.
And as $x^5 -m =0implies x^5 = mimplies x =sqrt [5]m$ so that is the only solution.
$endgroup$
add a comment
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5 Answers
5
active
oldest
votes
5 Answers
5
active
oldest
votes
active
oldest
votes
active
oldest
votes
$begingroup$
In fact we can even achieve this with a polynomial with rational coefficients: [Edit: After I wrote this answer, OP added the rationality of the coefficients as a condition.]
The Rational Root Theorem implies that $$x^5 - 2$$ has no rational roots, but since its degree is odd, it has at least one real---and hence irrational---root. (In fact, can replace $2$ here with any rational number that is not a perfect $5$th power of a rational number.)
$endgroup$
1
$begingroup$
in fact with integer coefficients
$endgroup$
– J. W. Tanner
10 hours ago
1
$begingroup$
Indeed! That said, we can always clear the denominators of any rational polynomial by multiplying by their $operatornamelcm$, and this operation preserves the roots. (But it's true that this example is a monic polynomial with integer coefficients.)
$endgroup$
– Travis
10 hours ago
add a comment
|
$begingroup$
In fact we can even achieve this with a polynomial with rational coefficients: [Edit: After I wrote this answer, OP added the rationality of the coefficients as a condition.]
The Rational Root Theorem implies that $$x^5 - 2$$ has no rational roots, but since its degree is odd, it has at least one real---and hence irrational---root. (In fact, can replace $2$ here with any rational number that is not a perfect $5$th power of a rational number.)
$endgroup$
1
$begingroup$
in fact with integer coefficients
$endgroup$
– J. W. Tanner
10 hours ago
1
$begingroup$
Indeed! That said, we can always clear the denominators of any rational polynomial by multiplying by their $operatornamelcm$, and this operation preserves the roots. (But it's true that this example is a monic polynomial with integer coefficients.)
$endgroup$
– Travis
10 hours ago
add a comment
|
$begingroup$
In fact we can even achieve this with a polynomial with rational coefficients: [Edit: After I wrote this answer, OP added the rationality of the coefficients as a condition.]
The Rational Root Theorem implies that $$x^5 - 2$$ has no rational roots, but since its degree is odd, it has at least one real---and hence irrational---root. (In fact, can replace $2$ here with any rational number that is not a perfect $5$th power of a rational number.)
$endgroup$
In fact we can even achieve this with a polynomial with rational coefficients: [Edit: After I wrote this answer, OP added the rationality of the coefficients as a condition.]
The Rational Root Theorem implies that $$x^5 - 2$$ has no rational roots, but since its degree is odd, it has at least one real---and hence irrational---root. (In fact, can replace $2$ here with any rational number that is not a perfect $5$th power of a rational number.)
edited 10 hours ago
answered 10 hours ago
TravisTravis
69.9k8 gold badges77 silver badges162 bronze badges
69.9k8 gold badges77 silver badges162 bronze badges
1
$begingroup$
in fact with integer coefficients
$endgroup$
– J. W. Tanner
10 hours ago
1
$begingroup$
Indeed! That said, we can always clear the denominators of any rational polynomial by multiplying by their $operatornamelcm$, and this operation preserves the roots. (But it's true that this example is a monic polynomial with integer coefficients.)
$endgroup$
– Travis
10 hours ago
add a comment
|
1
$begingroup$
in fact with integer coefficients
$endgroup$
– J. W. Tanner
10 hours ago
1
$begingroup$
Indeed! That said, we can always clear the denominators of any rational polynomial by multiplying by their $operatornamelcm$, and this operation preserves the roots. (But it's true that this example is a monic polynomial with integer coefficients.)
$endgroup$
– Travis
10 hours ago
1
1
$begingroup$
in fact with integer coefficients
$endgroup$
– J. W. Tanner
10 hours ago
$begingroup$
in fact with integer coefficients
$endgroup$
– J. W. Tanner
10 hours ago
1
1
$begingroup$
Indeed! That said, we can always clear the denominators of any rational polynomial by multiplying by their $operatornamelcm$, and this operation preserves the roots. (But it's true that this example is a monic polynomial with integer coefficients.)
$endgroup$
– Travis
10 hours ago
$begingroup$
Indeed! That said, we can always clear the denominators of any rational polynomial by multiplying by their $operatornamelcm$, and this operation preserves the roots. (But it's true that this example is a monic polynomial with integer coefficients.)
$endgroup$
– Travis
10 hours ago
add a comment
|
$begingroup$
That is pretty easy, if there are not other propertys required. Just consider a polynomial like:
$(x-sqrt2)^5$
$endgroup$
$begingroup$
That doesn't have rational coefficients.
$endgroup$
– fleablood
5 hours ago
$begingroup$
@fleablood OP added the requirement that the coefficients be rational a few minutes after this answer was posted.
$endgroup$
– Travis
3 hours ago
add a comment
|
$begingroup$
That is pretty easy, if there are not other propertys required. Just consider a polynomial like:
$(x-sqrt2)^5$
$endgroup$
$begingroup$
That doesn't have rational coefficients.
$endgroup$
– fleablood
5 hours ago
$begingroup$
@fleablood OP added the requirement that the coefficients be rational a few minutes after this answer was posted.
$endgroup$
– Travis
3 hours ago
add a comment
|
$begingroup$
That is pretty easy, if there are not other propertys required. Just consider a polynomial like:
$(x-sqrt2)^5$
$endgroup$
That is pretty easy, if there are not other propertys required. Just consider a polynomial like:
$(x-sqrt2)^5$
answered 10 hours ago
CornmanCornman
6,1612 gold badges13 silver badges33 bronze badges
6,1612 gold badges13 silver badges33 bronze badges
$begingroup$
That doesn't have rational coefficients.
$endgroup$
– fleablood
5 hours ago
$begingroup$
@fleablood OP added the requirement that the coefficients be rational a few minutes after this answer was posted.
$endgroup$
– Travis
3 hours ago
add a comment
|
$begingroup$
That doesn't have rational coefficients.
$endgroup$
– fleablood
5 hours ago
$begingroup$
@fleablood OP added the requirement that the coefficients be rational a few minutes after this answer was posted.
$endgroup$
– Travis
3 hours ago
$begingroup$
That doesn't have rational coefficients.
$endgroup$
– fleablood
5 hours ago
$begingroup$
That doesn't have rational coefficients.
$endgroup$
– fleablood
5 hours ago
$begingroup$
@fleablood OP added the requirement that the coefficients be rational a few minutes after this answer was posted.
$endgroup$
– Travis
3 hours ago
$begingroup$
@fleablood OP added the requirement that the coefficients be rational a few minutes after this answer was posted.
$endgroup$
– Travis
3 hours ago
add a comment
|
$begingroup$
If $alpha$ is irrational, then the polynomial $(x-alpha)^5$ has degree $5$, and the only (repeated) root is irrational.
$endgroup$
2
$begingroup$
More generally, $(x-a_1)(x-a_2)(x-a_3)(x-a_4)(x-a_5)$ for any irrational $a_1, dots, a_5$.
$endgroup$
– 79037662
10 hours ago
$begingroup$
I realize now that I might have phrased the question badly- it is only considering polynomials with rational coefficients.
$endgroup$
– Diba
10 hours ago
1
$begingroup$
@DibaHeydary: In that case, see the answer by Travis
$endgroup$
– J. W. Tanner
10 hours ago
add a comment
|
$begingroup$
If $alpha$ is irrational, then the polynomial $(x-alpha)^5$ has degree $5$, and the only (repeated) root is irrational.
$endgroup$
2
$begingroup$
More generally, $(x-a_1)(x-a_2)(x-a_3)(x-a_4)(x-a_5)$ for any irrational $a_1, dots, a_5$.
$endgroup$
– 79037662
10 hours ago
$begingroup$
I realize now that I might have phrased the question badly- it is only considering polynomials with rational coefficients.
$endgroup$
– Diba
10 hours ago
1
$begingroup$
@DibaHeydary: In that case, see the answer by Travis
$endgroup$
– J. W. Tanner
10 hours ago
add a comment
|
$begingroup$
If $alpha$ is irrational, then the polynomial $(x-alpha)^5$ has degree $5$, and the only (repeated) root is irrational.
$endgroup$
If $alpha$ is irrational, then the polynomial $(x-alpha)^5$ has degree $5$, and the only (repeated) root is irrational.
answered 10 hours ago
J. W. TannerJ. W. Tanner
16.9k1 gold badge12 silver badges35 bronze badges
16.9k1 gold badge12 silver badges35 bronze badges
2
$begingroup$
More generally, $(x-a_1)(x-a_2)(x-a_3)(x-a_4)(x-a_5)$ for any irrational $a_1, dots, a_5$.
$endgroup$
– 79037662
10 hours ago
$begingroup$
I realize now that I might have phrased the question badly- it is only considering polynomials with rational coefficients.
$endgroup$
– Diba
10 hours ago
1
$begingroup$
@DibaHeydary: In that case, see the answer by Travis
$endgroup$
– J. W. Tanner
10 hours ago
add a comment
|
2
$begingroup$
More generally, $(x-a_1)(x-a_2)(x-a_3)(x-a_4)(x-a_5)$ for any irrational $a_1, dots, a_5$.
$endgroup$
– 79037662
10 hours ago
$begingroup$
I realize now that I might have phrased the question badly- it is only considering polynomials with rational coefficients.
$endgroup$
– Diba
10 hours ago
1
$begingroup$
@DibaHeydary: In that case, see the answer by Travis
$endgroup$
– J. W. Tanner
10 hours ago
2
2
$begingroup$
More generally, $(x-a_1)(x-a_2)(x-a_3)(x-a_4)(x-a_5)$ for any irrational $a_1, dots, a_5$.
$endgroup$
– 79037662
10 hours ago
$begingroup$
More generally, $(x-a_1)(x-a_2)(x-a_3)(x-a_4)(x-a_5)$ for any irrational $a_1, dots, a_5$.
$endgroup$
– 79037662
10 hours ago
$begingroup$
I realize now that I might have phrased the question badly- it is only considering polynomials with rational coefficients.
$endgroup$
– Diba
10 hours ago
$begingroup$
I realize now that I might have phrased the question badly- it is only considering polynomials with rational coefficients.
$endgroup$
– Diba
10 hours ago
1
1
$begingroup$
@DibaHeydary: In that case, see the answer by Travis
$endgroup$
– J. W. Tanner
10 hours ago
$begingroup$
@DibaHeydary: In that case, see the answer by Travis
$endgroup$
– J. W. Tanner
10 hours ago
add a comment
|
$begingroup$
$$ x^5 + x^4 - 4 x^3 - 3 x^2 + 3 x + 1 $$
Five real irrational roots,
$$ 2 cos left( frac2k
pi11 right) $$
If you prefer the roots to be $cos( 2k pi /11),$ adjust the quintic to
$$ 32x^5 + 16x^4 - 32 x^3 - 12 x^2 + 6 x + 1 $$
gp-pari:
? x = cos( 2 * Pi / 11)
%1 = 0.8412535328311811688618116489
? f = 32 * x^5 + 16 * x^4 - 32 * x^3 - 12 * x^2 + 6 * x + 1
%2 = -1.009741959 E-28
?
? x = cos( 4 * Pi / 11)
%3 = 0.4154150130018864255292741493
? f = 32 * x^5 + 16 * x^4 - 32 * x^3 - 12 * x^2 + 6 * x + 1
%4 = -2.019483917 E-28
?
? x = cos( 6 * Pi / 11)
%5 = -0.1423148382732851404437926686
? f = 32 * x^5 + 16 * x^4 - 32 * x^3 - 12 * x^2 + 6 * x + 1
%6 = -7.57306469 E-29
?
? x = cos( 8 * Pi / 11)
%7 = -0.6548607339452850640569250725
? f = 32 * x^5 + 16 * x^4 - 32 * x^3 - 12 * x^2 + 6 * x + 1
%8 = 0.E-28
?
=============================
$endgroup$
$begingroup$
I'm confused, how did you connect polynomials to triginometry? Through something like taylor series?
$endgroup$
– vikarjramun
2 hours ago
add a comment
|
$begingroup$
$$ x^5 + x^4 - 4 x^3 - 3 x^2 + 3 x + 1 $$
Five real irrational roots,
$$ 2 cos left( frac2k
pi11 right) $$
If you prefer the roots to be $cos( 2k pi /11),$ adjust the quintic to
$$ 32x^5 + 16x^4 - 32 x^3 - 12 x^2 + 6 x + 1 $$
gp-pari:
? x = cos( 2 * Pi / 11)
%1 = 0.8412535328311811688618116489
? f = 32 * x^5 + 16 * x^4 - 32 * x^3 - 12 * x^2 + 6 * x + 1
%2 = -1.009741959 E-28
?
? x = cos( 4 * Pi / 11)
%3 = 0.4154150130018864255292741493
? f = 32 * x^5 + 16 * x^4 - 32 * x^3 - 12 * x^2 + 6 * x + 1
%4 = -2.019483917 E-28
?
? x = cos( 6 * Pi / 11)
%5 = -0.1423148382732851404437926686
? f = 32 * x^5 + 16 * x^4 - 32 * x^3 - 12 * x^2 + 6 * x + 1
%6 = -7.57306469 E-29
?
? x = cos( 8 * Pi / 11)
%7 = -0.6548607339452850640569250725
? f = 32 * x^5 + 16 * x^4 - 32 * x^3 - 12 * x^2 + 6 * x + 1
%8 = 0.E-28
?
=============================
$endgroup$
$begingroup$
I'm confused, how did you connect polynomials to triginometry? Through something like taylor series?
$endgroup$
– vikarjramun
2 hours ago
add a comment
|
$begingroup$
$$ x^5 + x^4 - 4 x^3 - 3 x^2 + 3 x + 1 $$
Five real irrational roots,
$$ 2 cos left( frac2k
pi11 right) $$
If you prefer the roots to be $cos( 2k pi /11),$ adjust the quintic to
$$ 32x^5 + 16x^4 - 32 x^3 - 12 x^2 + 6 x + 1 $$
gp-pari:
? x = cos( 2 * Pi / 11)
%1 = 0.8412535328311811688618116489
? f = 32 * x^5 + 16 * x^4 - 32 * x^3 - 12 * x^2 + 6 * x + 1
%2 = -1.009741959 E-28
?
? x = cos( 4 * Pi / 11)
%3 = 0.4154150130018864255292741493
? f = 32 * x^5 + 16 * x^4 - 32 * x^3 - 12 * x^2 + 6 * x + 1
%4 = -2.019483917 E-28
?
? x = cos( 6 * Pi / 11)
%5 = -0.1423148382732851404437926686
? f = 32 * x^5 + 16 * x^4 - 32 * x^3 - 12 * x^2 + 6 * x + 1
%6 = -7.57306469 E-29
?
? x = cos( 8 * Pi / 11)
%7 = -0.6548607339452850640569250725
? f = 32 * x^5 + 16 * x^4 - 32 * x^3 - 12 * x^2 + 6 * x + 1
%8 = 0.E-28
?
=============================
$endgroup$
$$ x^5 + x^4 - 4 x^3 - 3 x^2 + 3 x + 1 $$
Five real irrational roots,
$$ 2 cos left( frac2k
pi11 right) $$
If you prefer the roots to be $cos( 2k pi /11),$ adjust the quintic to
$$ 32x^5 + 16x^4 - 32 x^3 - 12 x^2 + 6 x + 1 $$
gp-pari:
? x = cos( 2 * Pi / 11)
%1 = 0.8412535328311811688618116489
? f = 32 * x^5 + 16 * x^4 - 32 * x^3 - 12 * x^2 + 6 * x + 1
%2 = -1.009741959 E-28
?
? x = cos( 4 * Pi / 11)
%3 = 0.4154150130018864255292741493
? f = 32 * x^5 + 16 * x^4 - 32 * x^3 - 12 * x^2 + 6 * x + 1
%4 = -2.019483917 E-28
?
? x = cos( 6 * Pi / 11)
%5 = -0.1423148382732851404437926686
? f = 32 * x^5 + 16 * x^4 - 32 * x^3 - 12 * x^2 + 6 * x + 1
%6 = -7.57306469 E-29
?
? x = cos( 8 * Pi / 11)
%7 = -0.6548607339452850640569250725
? f = 32 * x^5 + 16 * x^4 - 32 * x^3 - 12 * x^2 + 6 * x + 1
%8 = 0.E-28
?
=============================
edited 5 hours ago
answered 10 hours ago
Will JagyWill Jagy
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109k5 gold badges107 silver badges209 bronze badges
$begingroup$
I'm confused, how did you connect polynomials to triginometry? Through something like taylor series?
$endgroup$
– vikarjramun
2 hours ago
add a comment
|
$begingroup$
I'm confused, how did you connect polynomials to triginometry? Through something like taylor series?
$endgroup$
– vikarjramun
2 hours ago
$begingroup$
I'm confused, how did you connect polynomials to triginometry? Through something like taylor series?
$endgroup$
– vikarjramun
2 hours ago
$begingroup$
I'm confused, how did you connect polynomials to triginometry? Through something like taylor series?
$endgroup$
– vikarjramun
2 hours ago
add a comment
|
$begingroup$
Well, $sqrt[5]m$ is irrational if $m$ is an integer that isn't a perfect power of $5$.
And $sqrt[5]m$ is a solution to $x^5 -m =0$.
And as $x^5 -m =0implies x^5 = mimplies x =sqrt [5]m$ so that is the only solution.
$endgroup$
add a comment
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$begingroup$
Well, $sqrt[5]m$ is irrational if $m$ is an integer that isn't a perfect power of $5$.
And $sqrt[5]m$ is a solution to $x^5 -m =0$.
And as $x^5 -m =0implies x^5 = mimplies x =sqrt [5]m$ so that is the only solution.
$endgroup$
add a comment
|
$begingroup$
Well, $sqrt[5]m$ is irrational if $m$ is an integer that isn't a perfect power of $5$.
And $sqrt[5]m$ is a solution to $x^5 -m =0$.
And as $x^5 -m =0implies x^5 = mimplies x =sqrt [5]m$ so that is the only solution.
$endgroup$
Well, $sqrt[5]m$ is irrational if $m$ is an integer that isn't a perfect power of $5$.
And $sqrt[5]m$ is a solution to $x^5 -m =0$.
And as $x^5 -m =0implies x^5 = mimplies x =sqrt [5]m$ so that is the only solution.
answered 5 hours ago
fleabloodfleablood
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81.3k2 gold badges32 silver badges99 bronze badges
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$begingroup$
how about $(x-pi)^5$ or $(x-e)^5$ or $(x-sqrt2)^5$?
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– J. W. Tanner
11 hours ago
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Or even just $x^5-2$?
$endgroup$
– Lord Shark the Unknown
10 hours ago