sinx/(1+sinx)的积分

1个回答

  • 答:

    原式

    =∫ (1+sinx-1)/(1+sinx) dx

    =∫ 1-1/(1+sinx)dx

    =x- ∫ 1/(1+cos(x-π/2))dx

    =x- ∫ 1/(1+2[cos(x/2-π/4)]^2-1) dx

    =x-1/2*∫ 1/[(cos(x/2-π/4)]^2 dx

    =x-1/2*2tan(x/2-π/4) + C

    =x-tan(x/2-π/4) + C

    注:答案里tan(x/2-π/4)可以做不同的化简,即答案的形式不唯一.