Question

$cos^{2}(2 pi +t)+ sin^{2} ( frac{3 pi }{2} - t)$ = ? (упростить выражение)

Answer 1

cos(2pi + t) cos(2pi + t) + sin (3pi/2 - t) sin (3pi/2 - t) = 
= cos (t) cos (t) - cos (t) * ( - cost) = 
= cos^2t + cos^2t = 2cos^2t