积分式化为:√((1-x)/(1+x)=(1-x)/√(1-x^2)=1/√(1-x^2)-x/√(1-x^2)
前部分积分=arcsin(x),后部分积分=∫-x/√(1-x^2)dx=∫1/2*1/√(1-x^2)d(1-x^2)
=∫d√(1-x^2)= √(1-x^2)
总积分=arcsin(x)+ √(1-x^2)+c常数
令x=cost
则原式=∫√(1-cost)/(1+cost)dcost
=∫√(1-cos^2t)/(1+cost)^2dcost
∫-sin^2t/(1+cost)dt
=∫(cos^2t-1)/(1+cost)dt
=∫cost-1dt
=-sint-t+c
=-√(1-x^2) - arccost + c