Упростите выражение: a) sin^2(π/2 + t) + sin^2(π – t) б) cos(π/2-t)ctg(-t) / sin(π/2+t)
A) sin^2(π/2 + t) + sin^2(π – t) = cos^2t + sin^2t = 1 б) cos(π/2-t)ctg(-t) / sin(π/2+t) =(sint)*(cost/sint) / cost = 1