Question

Решить предел!!!!!!!!!!!!

Answer 1

$\lim_{x \to 0} \dfrac{xtg(5x)}{cosx-cos^3x}= \lim_{x \to 0} \dfrac{xtg(5x)}{cosx(1-cos^2x)}=\lim_{x \to 0} \dfrac{x*5x}{cosx*sin^2x}=\lim_{x \to 0} \dfrac{x*5x}{1*x^2}=5$