SOLUTION: Hi i am trying to find the 2nd order partial derivatives for {{{f(x,y)=e^(ax)(cosby)}}} for both fxx and fyy

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Question 432408: Hi i am trying to find the 2nd order partial derivatives for
f%28x%2Cy%29=e%5E%28ax%29%28cosby%29
for both fxx and fyy

Answer by belle3833(46) About Me  (Show Source):
You can put this solution on YOUR website!

Treat y as a constant and differentiate
fx=cos%28by%29+ae%5E%28ax%29
fxx=cos%28by%29a%5E%282%29e%5E%28ax%29

Now treat x as a constant and differentiate
fy=-be%5E%28ax%29sin%28by%29
fyy=-b%5E%282%29e%5E%28ax%29cos%28by%29