(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

f(x,y)=2Sin x Cos y

g(x,y) = 2Cos x Sin y

verify that d(fg)/dx = g(x,y) df/dx + f(x,y) dg/dx

3. The attempt at a solution

first of all I worked out the partials derivatives in respective to x and y, for both functions

df/dx = 2Cos x (but I've a gut feeling that it should be 2Sin x * Cos x)

df/dy = -Sin y (but I've a gut feeling that it should be Cos y * -Sin y)

dg/dx=-2Sin x (but I've a gut feeling that it should be 2Cos x * -Sin x)

dg/dy=Cos y (but I've a gut feeling that it should be Sin y * Cos y)

but I don't get how to verify d(fg)/dx = g(x,y) df/dx + f(x,y) dg/dx

can someone walk me through what does the question is asking about?

Thanks

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# Homework Help: Verify partial derivatives

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