Proving eulers formulae question

Question

F(x) = (x-x²) from x=- pi to x = pi

We have to prove by euler's formulae ..

Any one help

Answer 1

Your question is not clear.

What does your first line mean? Are you somehow indicating an integral? What does the function have to do with Euler's formula?

Euler's formula is most easily proved by looking at the Taylor expansions of e^x, cos x and sin x.