Differential equations

Solve the ordinary differential equation $\frac{d^{2}y }{dx^{2} } =y$  for y as a function of x. (Note that this is equivalent to y" = y.)

Solve the partial differential equation $ \frac{?^{2} f}{?x?y} = xy$  for f as a function of x and y.

Answer

Answers can be viewed only if
  1. The questioner was satisfied and accepted the answer, or
  2. The answer was disputed, but the judge evaluated it as 100% correct.
View the answer
The answer is accepted.