用换元积分法求∫√[(x+1)-1]⼀[√(x+1)+1]dx的不定积分

2025-04-06 00:43:38
推荐回答(2个)
回答1:

令√(x+1)=u,则:x+1=u^2,∴dx=2udu。
∴∫{[√(x+1)-1]/[√(x+1)+1]}dx
=2∫[(u-1)/(u+1)]udu
=2∫[(u+1 -2)/(u+1)]udu
= 2∫udu-4∫[u/(u+1)]du
= u^2-4∫[(u+1-1)/(u+1)]du
=x+1-4∫du+4∫[1/(u+1)]du
=x+1-4u+4ln|u+1|+C
=x-4√(x+1)+4|√(x+1)+1|+C。

回答2:

把那式子照下来呢,看着迷糊