计算过程如下:
由奇偶性,∫(π/2 ,-π/2) √[(cosx)^3-(cosx)^5]dx=2∫(π/2,0) √[(cosx)^3×(sinx)^2]dx=2∫(π/2,0) (cosx)^(3/2) × sinx dx = 2∫(π/2,0) (cosx)^(3/2) d(-cosx),所以被积函数的原函数是-2/5×(cosx)^(5/2),带入上下限,相减,得结果2/5
∫(π/2 ,-π/2)√[(cosx)^3-(cosx)^5]dx
=2∫(π/2 ,0)√[(cosx)^3-(cosx)^5]dx
=2∫(π/2 ,0)√[(cosx)^3*sinxdx
=-2∫(π/2 ,0)√[(cosx)^3*dcosx
=-4/5(cosx)^(5/2)|(π/2 ,0) 上限为π/2 ,下限为0
=4/5