What is the positive integral solution of $x^2+y^2= qz^2$?












1












$begingroup$


Is there a standard method to find positive integral solutions of the equation $x^2+y^2= qz^2$, where $q$ is a positive integral constant? If yes, then would someone please show it to me? Actually I had come across a problem in which we had to find integral solutions of $a^2+b^2=2c^2$ which was done by changing it to $(a-2/2)^2+(b-2/2)^2= c^2$ and using the parametric form of Pythogorean triplets but what if we had other numbers such as 4 or 5 in place of q?










share|cite|improve this question











$endgroup$












  • $begingroup$
    The left hand side looks like an ellipse, by swapping x and y you would get another ellipse, so I think you get a family of solutions.
    $endgroup$
    – Emil
    Dec 19 '18 at 7:26






  • 1




    $begingroup$
    en.wikipedia.org/wiki/Hasse_principle
    $endgroup$
    – metamorphy
    Dec 19 '18 at 8:04










  • $begingroup$
    If you can find one solution then the method of parametrizing Pythagorean triples (draw lines with rational slope thru $(1,0)$ and find the other point of intersection with the unit circle) generalizes to this case as well. You will use the ellipse $x^2+py^2=q$ instead.
    $endgroup$
    – Jyrki Lahtonen
    Dec 19 '18 at 13:37






  • 1




    $begingroup$
    @Jyrki the rational slope method does give all rational solutions; multiplying out it gives a Pythagorean triple type of formula. If you then say to divide out by the gcd of x,y,z you do get all primitive triples. More work: for such a parametrization, with coprime $u,v$ the set of gcd's of $x,y,z$ is finite. For each, a new integer parametrization may be produced.. compare answer and my comment at math.stackexchange.com/questions/3044517/…
    $endgroup$
    – Will Jagy
    Dec 19 '18 at 17:54






  • 1




    $begingroup$
    artofproblemsolving.com/community/…
    $endgroup$
    – individ
    Dec 21 '18 at 5:50
















1












$begingroup$


Is there a standard method to find positive integral solutions of the equation $x^2+y^2= qz^2$, where $q$ is a positive integral constant? If yes, then would someone please show it to me? Actually I had come across a problem in which we had to find integral solutions of $a^2+b^2=2c^2$ which was done by changing it to $(a-2/2)^2+(b-2/2)^2= c^2$ and using the parametric form of Pythogorean triplets but what if we had other numbers such as 4 or 5 in place of q?










share|cite|improve this question











$endgroup$












  • $begingroup$
    The left hand side looks like an ellipse, by swapping x and y you would get another ellipse, so I think you get a family of solutions.
    $endgroup$
    – Emil
    Dec 19 '18 at 7:26






  • 1




    $begingroup$
    en.wikipedia.org/wiki/Hasse_principle
    $endgroup$
    – metamorphy
    Dec 19 '18 at 8:04










  • $begingroup$
    If you can find one solution then the method of parametrizing Pythagorean triples (draw lines with rational slope thru $(1,0)$ and find the other point of intersection with the unit circle) generalizes to this case as well. You will use the ellipse $x^2+py^2=q$ instead.
    $endgroup$
    – Jyrki Lahtonen
    Dec 19 '18 at 13:37






  • 1




    $begingroup$
    @Jyrki the rational slope method does give all rational solutions; multiplying out it gives a Pythagorean triple type of formula. If you then say to divide out by the gcd of x,y,z you do get all primitive triples. More work: for such a parametrization, with coprime $u,v$ the set of gcd's of $x,y,z$ is finite. For each, a new integer parametrization may be produced.. compare answer and my comment at math.stackexchange.com/questions/3044517/…
    $endgroup$
    – Will Jagy
    Dec 19 '18 at 17:54






  • 1




    $begingroup$
    artofproblemsolving.com/community/…
    $endgroup$
    – individ
    Dec 21 '18 at 5:50














1












1








1


1



$begingroup$


Is there a standard method to find positive integral solutions of the equation $x^2+y^2= qz^2$, where $q$ is a positive integral constant? If yes, then would someone please show it to me? Actually I had come across a problem in which we had to find integral solutions of $a^2+b^2=2c^2$ which was done by changing it to $(a-2/2)^2+(b-2/2)^2= c^2$ and using the parametric form of Pythogorean triplets but what if we had other numbers such as 4 or 5 in place of q?










share|cite|improve this question











$endgroup$




Is there a standard method to find positive integral solutions of the equation $x^2+y^2= qz^2$, where $q$ is a positive integral constant? If yes, then would someone please show it to me? Actually I had come across a problem in which we had to find integral solutions of $a^2+b^2=2c^2$ which was done by changing it to $(a-2/2)^2+(b-2/2)^2= c^2$ and using the parametric form of Pythogorean triplets but what if we had other numbers such as 4 or 5 in place of q?







number-theory diophantine-equations






share|cite|improve this question















share|cite|improve this question













share|cite|improve this question




share|cite|improve this question








edited Dec 20 '18 at 18:53







Shashwat1337

















asked Dec 19 '18 at 7:10









Shashwat1337Shashwat1337

959




959












  • $begingroup$
    The left hand side looks like an ellipse, by swapping x and y you would get another ellipse, so I think you get a family of solutions.
    $endgroup$
    – Emil
    Dec 19 '18 at 7:26






  • 1




    $begingroup$
    en.wikipedia.org/wiki/Hasse_principle
    $endgroup$
    – metamorphy
    Dec 19 '18 at 8:04










  • $begingroup$
    If you can find one solution then the method of parametrizing Pythagorean triples (draw lines with rational slope thru $(1,0)$ and find the other point of intersection with the unit circle) generalizes to this case as well. You will use the ellipse $x^2+py^2=q$ instead.
    $endgroup$
    – Jyrki Lahtonen
    Dec 19 '18 at 13:37






  • 1




    $begingroup$
    @Jyrki the rational slope method does give all rational solutions; multiplying out it gives a Pythagorean triple type of formula. If you then say to divide out by the gcd of x,y,z you do get all primitive triples. More work: for such a parametrization, with coprime $u,v$ the set of gcd's of $x,y,z$ is finite. For each, a new integer parametrization may be produced.. compare answer and my comment at math.stackexchange.com/questions/3044517/…
    $endgroup$
    – Will Jagy
    Dec 19 '18 at 17:54






  • 1




    $begingroup$
    artofproblemsolving.com/community/…
    $endgroup$
    – individ
    Dec 21 '18 at 5:50


















  • $begingroup$
    The left hand side looks like an ellipse, by swapping x and y you would get another ellipse, so I think you get a family of solutions.
    $endgroup$
    – Emil
    Dec 19 '18 at 7:26






  • 1




    $begingroup$
    en.wikipedia.org/wiki/Hasse_principle
    $endgroup$
    – metamorphy
    Dec 19 '18 at 8:04










  • $begingroup$
    If you can find one solution then the method of parametrizing Pythagorean triples (draw lines with rational slope thru $(1,0)$ and find the other point of intersection with the unit circle) generalizes to this case as well. You will use the ellipse $x^2+py^2=q$ instead.
    $endgroup$
    – Jyrki Lahtonen
    Dec 19 '18 at 13:37






  • 1




    $begingroup$
    @Jyrki the rational slope method does give all rational solutions; multiplying out it gives a Pythagorean triple type of formula. If you then say to divide out by the gcd of x,y,z you do get all primitive triples. More work: for such a parametrization, with coprime $u,v$ the set of gcd's of $x,y,z$ is finite. For each, a new integer parametrization may be produced.. compare answer and my comment at math.stackexchange.com/questions/3044517/…
    $endgroup$
    – Will Jagy
    Dec 19 '18 at 17:54






  • 1




    $begingroup$
    artofproblemsolving.com/community/…
    $endgroup$
    – individ
    Dec 21 '18 at 5:50
















$begingroup$
The left hand side looks like an ellipse, by swapping x and y you would get another ellipse, so I think you get a family of solutions.
$endgroup$
– Emil
Dec 19 '18 at 7:26




$begingroup$
The left hand side looks like an ellipse, by swapping x and y you would get another ellipse, so I think you get a family of solutions.
$endgroup$
– Emil
Dec 19 '18 at 7:26




1




1




$begingroup$
en.wikipedia.org/wiki/Hasse_principle
$endgroup$
– metamorphy
Dec 19 '18 at 8:04




$begingroup$
en.wikipedia.org/wiki/Hasse_principle
$endgroup$
– metamorphy
Dec 19 '18 at 8:04












$begingroup$
If you can find one solution then the method of parametrizing Pythagorean triples (draw lines with rational slope thru $(1,0)$ and find the other point of intersection with the unit circle) generalizes to this case as well. You will use the ellipse $x^2+py^2=q$ instead.
$endgroup$
– Jyrki Lahtonen
Dec 19 '18 at 13:37




$begingroup$
If you can find one solution then the method of parametrizing Pythagorean triples (draw lines with rational slope thru $(1,0)$ and find the other point of intersection with the unit circle) generalizes to this case as well. You will use the ellipse $x^2+py^2=q$ instead.
$endgroup$
– Jyrki Lahtonen
Dec 19 '18 at 13:37




1




1




$begingroup$
@Jyrki the rational slope method does give all rational solutions; multiplying out it gives a Pythagorean triple type of formula. If you then say to divide out by the gcd of x,y,z you do get all primitive triples. More work: for such a parametrization, with coprime $u,v$ the set of gcd's of $x,y,z$ is finite. For each, a new integer parametrization may be produced.. compare answer and my comment at math.stackexchange.com/questions/3044517/…
$endgroup$
– Will Jagy
Dec 19 '18 at 17:54




$begingroup$
@Jyrki the rational slope method does give all rational solutions; multiplying out it gives a Pythagorean triple type of formula. If you then say to divide out by the gcd of x,y,z you do get all primitive triples. More work: for such a parametrization, with coprime $u,v$ the set of gcd's of $x,y,z$ is finite. For each, a new integer parametrization may be produced.. compare answer and my comment at math.stackexchange.com/questions/3044517/…
$endgroup$
– Will Jagy
Dec 19 '18 at 17:54




1




1




$begingroup$
artofproblemsolving.com/community/…
$endgroup$
– individ
Dec 21 '18 at 5:50




$begingroup$
artofproblemsolving.com/community/…
$endgroup$
– individ
Dec 21 '18 at 5:50










0






active

oldest

votes











Your Answer





StackExchange.ifUsing("editor", function () {
return StackExchange.using("mathjaxEditing", function () {
StackExchange.MarkdownEditor.creationCallbacks.add(function (editor, postfix) {
StackExchange.mathjaxEditing.prepareWmdForMathJax(editor, postfix, [["$", "$"], ["\\(","\\)"]]);
});
});
}, "mathjax-editing");

StackExchange.ready(function() {
var channelOptions = {
tags: "".split(" "),
id: "69"
};
initTagRenderer("".split(" "), "".split(" "), channelOptions);

StackExchange.using("externalEditor", function() {
// Have to fire editor after snippets, if snippets enabled
if (StackExchange.settings.snippets.snippetsEnabled) {
StackExchange.using("snippets", function() {
createEditor();
});
}
else {
createEditor();
}
});

function createEditor() {
StackExchange.prepareEditor({
heartbeatType: 'answer',
autoActivateHeartbeat: false,
convertImagesToLinks: true,
noModals: true,
showLowRepImageUploadWarning: true,
reputationToPostImages: 10,
bindNavPrevention: true,
postfix: "",
imageUploader: {
brandingHtml: "Powered by u003ca class="icon-imgur-white" href="https://imgur.com/"u003eu003c/au003e",
contentPolicyHtml: "User contributions licensed under u003ca href="https://creativecommons.org/licenses/by-sa/3.0/"u003ecc by-sa 3.0 with attribution requiredu003c/au003e u003ca href="https://stackoverflow.com/legal/content-policy"u003e(content policy)u003c/au003e",
allowUrls: true
},
noCode: true, onDemand: true,
discardSelector: ".discard-answer"
,immediatelyShowMarkdownHelp:true
});


}
});














draft saved

draft discarded


















StackExchange.ready(
function () {
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fmath.stackexchange.com%2fquestions%2f3046123%2fwhat-is-the-positive-integral-solution-of-x2y2-qz2%23new-answer', 'question_page');
}
);

Post as a guest















Required, but never shown

























0






active

oldest

votes








0






active

oldest

votes









active

oldest

votes






active

oldest

votes
















draft saved

draft discarded




















































Thanks for contributing an answer to Mathematics Stack Exchange!


  • Please be sure to answer the question. Provide details and share your research!

But avoid



  • Asking for help, clarification, or responding to other answers.

  • Making statements based on opinion; back them up with references or personal experience.


Use MathJax to format equations. MathJax reference.


To learn more, see our tips on writing great answers.




draft saved


draft discarded














StackExchange.ready(
function () {
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fmath.stackexchange.com%2fquestions%2f3046123%2fwhat-is-the-positive-integral-solution-of-x2y2-qz2%23new-answer', 'question_page');
}
);

Post as a guest















Required, but never shown





















































Required, but never shown














Required, but never shown












Required, but never shown







Required, but never shown

































Required, but never shown














Required, but never shown












Required, but never shown







Required, but never shown







Popular posts from this blog

Bundesstraße 106

Verónica Boquete

Ida-Boy-Ed-Garten