Question

f(x)=cos2x, x0=pi/6
f'(x)=?
ma puteti ajuta va rog?

Answer 1

f'(x)=$\lim_{x \to \infty} \frac{f(x)-f(x0)}{x-x0} = \frac{cos2x-cos2 \frac{ \pi }{6} }{x- \frac{ \pi }{6} }$