求定积分!请给出具体步骤!∫(π/2,0) (cosx)^2*(sinx)^3dx
问题描述：
求定积分!请给出具体步骤!∫(π/2,0) (cosx)^2*(sinx)^3dx
答
∫(π/2,0)(cosx)^2*(sinx)^3dx
=-∫(π/2,0)(cosx)^2*(sinx)^2d(cosx)
=∫(π/2,0)(cosx)^2*[(cosx)^2-1]d(cosx)
=∫(π/2,0)[(cosx)^4-(cosx)^2]d(cosx)
=(π/2,0)[(1/5)(cosx)^5-(1/3)(cosx)^3
=0-(1/5-1/3)
=2/15