# Math Help - Find Derivative of Rational Function

1. ## Find Derivative of Rational Function

Find derivative.

y = [cos(pix) + 1]/x

y' = - [pixsin(pix) minus cos(pix) + 1]/x^2

It's because it should be $\displaystyle \frac{ - \pi x \sin{( \pi x )} - \left[ \cos{( \pi x ) } + 1 \right] }{x^2}$.