Question

(1+tg^2a)cos^4a+sin^2a (упростить)

Answer 1

$(1+tg ^{2} \alpha )cos ^{4} \alpha +sin ^{2} \alpha = \frac{1}{cos ^{2} \alpha } cos ^{4} \alpha +sin ^{2} \alpha =cos ^{2} \alpha +sin ^{2} \alpha =1$