Răspunsuri

2014-06-12T20:32:09+03:00
F'(x)= \lim_{x \to \infty}  \frac{f(x)-f(x0)}{x-x0} = \frac{cos2x-cos2 \frac{ \pi }{6} }{x- \frac{ \pi }{6} }
am inlocui cos de 2x cu (1-sin^2 x)/2 si a dat -sin^2 x / x-pi/6 . De aici? ..