定积分∫(π/4→-π/4) tan^2x dx

问题描述:

定积分∫(π/4→-π/4) tan^2x dx
上π/4 下-π/4

原式=∫(π/4→-π/4) (sec²x-1)dx
=(tanx-x)(π/4→-π/4)
=2-π/2