Question

Lim (x стремится к П/2)
1+cos 2x / cos x

Answer 1

$displaystylelim_{xtofrac{pi}{2}}frac{1+cos2x}{cos{x}} = lim_{xtofrac{pi}{2}} frac{2cos^2x}{cos{x}} = \\ = 2lim_{xtofrac{pi}{2}}cos{x} = 2cdot0 = 0$