Question

Найти производную функци:y=log5cos7x

Answer 1

$y'=(log_5cos7x)'=frac{1}{cos7xcdotln5}cdot(cos7x)'=frac{1}{cos7xcdotln5}cdot(-sin7x)cdot(7x)'= \ =-frac{sin7x}{cos7xcdotln5}cdot7=-frac{7sin7x}{cos7xcdotln5}$