Question

化简三角函数[sin(α+pi)*cos(pi+α)*cos(α+2pi)]/[tan(pi+α)*cos^3(-α-p

Answer 1

原式=[(-sinα)(-cosα)cosα]/[tanα*(-cosα)^3]

=[sinα(cosα)^2]/[(sinα/cosα)(-cosα)^3]

=-1 。