Is f(xy)=e^(2y)sin(pix) a Solution to the Differential Equation Given?

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SUMMARY

The function f(xy) = e^(2y)sin(πx) does not satisfy the differential equation (fxy)² - fxx(fyy) = 4π²e^(4x). The computed derivatives are fxx = -πe^(2y)sin(πx), fyy = 4sin(πx)e^(2y), and fxy = 2πe^(2y)cos(πx). Upon simplification, the equation yields e^(4y)(sin²(πx) + πe^(4y)cos²(πx)) = πe^(4x), confirming that f(xy) is not a solution. The discussion suggests a potential typo in the original problem statement, proposing it may instead involve e^(4y).

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let f(xy)=e^(2y)sin(pix), is f a solution to (fxy)^2 -fxx(fyy)=4pi^2 e^(4x)


So I found fxx and fyy and fxy, which are -pi(e^(2y))sin(pix), 4sin(pix)e^(2y), 2pi(e^(2y))cos(pix) respectively,

When i reduced everything i got e^4y(sin^2(pix))+pie^4ycos^2(pix)=pie^(4x). I am assuming it is not a solution to 4pi^2 e^(4x) because first, it doesn't add up, and second, e^(4y) is never e^(4x). Am I right, I am not sure?
 
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You are right that it is not a solution, but I wonder whether it's because there is a typo in the question. Maybe it should say fxy2 -fxxfyy=4pi2 e4y
 
Yeah, me too. But the problem on the paper clearly states that. I'll bring it up to my professor. Thanks!
 

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