f(x)=tg^2x x0=п/6 решите

f(x)=tg^2(x)f '(x)=2tgx /cos^2(x)f '(x0)=2tg(п/6) / cos^2(п/6) = 2*(√3/3) / (√3/2)² = 2(√3/3) / (3/4) = (2√3/3) * (4/3)  = 8√3 / 9