Prove the Form of a Function












0












$begingroup$


I asked a related question in oder to tackle this problem by myself, but still couldn't find a way to solve it despite a lot of efforts.



A function $f : R^2 to R$ satisfies $f(tx,ty) = t^2f(x, y)$ for all $t,x,y in R$. Assuming that
$f$ is continuously twice differentiable, show that:
$$
f(x,y) = ax^2 + bxy + cy^2
$$
for some
constants $a,b,c in R$.










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  • $begingroup$
    Can somebody help me?
    $endgroup$
    – A Slow Learner
    Jan 16 at 2:36
















0












$begingroup$


I asked a related question in oder to tackle this problem by myself, but still couldn't find a way to solve it despite a lot of efforts.



A function $f : R^2 to R$ satisfies $f(tx,ty) = t^2f(x, y)$ for all $t,x,y in R$. Assuming that
$f$ is continuously twice differentiable, show that:
$$
f(x,y) = ax^2 + bxy + cy^2
$$
for some
constants $a,b,c in R$.










share|cite|improve this question









$endgroup$












  • $begingroup$
    Can somebody help me?
    $endgroup$
    – A Slow Learner
    Jan 16 at 2:36














0












0








0





$begingroup$


I asked a related question in oder to tackle this problem by myself, but still couldn't find a way to solve it despite a lot of efforts.



A function $f : R^2 to R$ satisfies $f(tx,ty) = t^2f(x, y)$ for all $t,x,y in R$. Assuming that
$f$ is continuously twice differentiable, show that:
$$
f(x,y) = ax^2 + bxy + cy^2
$$
for some
constants $a,b,c in R$.










share|cite|improve this question









$endgroup$




I asked a related question in oder to tackle this problem by myself, but still couldn't find a way to solve it despite a lot of efforts.



A function $f : R^2 to R$ satisfies $f(tx,ty) = t^2f(x, y)$ for all $t,x,y in R$. Assuming that
$f$ is continuously twice differentiable, show that:
$$
f(x,y) = ax^2 + bxy + cy^2
$$
for some
constants $a,b,c in R$.







calculus polynomials






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share|cite|improve this question











share|cite|improve this question




share|cite|improve this question










asked Jan 15 at 17:23









A Slow LearnerA Slow Learner

466313




466313












  • $begingroup$
    Can somebody help me?
    $endgroup$
    – A Slow Learner
    Jan 16 at 2:36


















  • $begingroup$
    Can somebody help me?
    $endgroup$
    – A Slow Learner
    Jan 16 at 2:36
















$begingroup$
Can somebody help me?
$endgroup$
– A Slow Learner
Jan 16 at 2:36




$begingroup$
Can somebody help me?
$endgroup$
– A Slow Learner
Jan 16 at 2:36










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