早教吧 育儿知识 作业答案 考试题库 百科 知识分享

求不定积分1/(1-x^2)^2

题目详情
求不定积分1/(1-x^2)^2
▼优质解答
答案和解析
令x = sinz,dx = cosz dz
∫ dx/(1 - x²)²
= ∫ 1/cos⁴z * (cosz dz)
= ∫ sec³z dz
= (1/2)secztanz + (1/2)ln|secz + tanz| + C
= (1/2)[x/√(1 - x²)][1/√(1 - x²)] + (1/2)ln|x/√(1 - x²) + 1/√(1 - x²)| + C
= x/[2(1 - x²)] + (1/2)ln|(1 + x)/√[(1 - x)(1 + x)]| + C
= x/[2(1 - x²)] + (1/2)ln|√(1 + x)/√(1 - x)| + C
= x/[2(1 - x²)] + (1/4)ln|(1 + x)/(1 - x)| + C