一道不定积分题求解∫1/(√x+1)dx

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一道不定积分题求解∫1/(√x+1)dx

一道不定积分题求解∫1/(√x+1)dx
一道不定积分题求解
∫1/(√x+1)dx

一道不定积分题求解∫1/(√x+1)dx
才用换元积分达,设√x=u x=u² 转化为∫1/(u+1)du²
=2∫u/(u+1)
=2∫1du-2∫1/(u+1)du
=2u-ln(u+1)+C 再把u换成√x就可以了,手机麻烦,不打了

换元,用t=√x
结果是:
2√x-2ln(√x+1)+c

=∫(0,2)∫(2,4),K(6-XY)DXDY
=∫(0,2)(-KX ^ 2/2 +(6K-Y)×)[2.4] DY
=∫(0,2)(-16K / 2 +(6K-Y)4 +4 k/2-(6K-Y)2)DY
=∫(0,2),( - 8K +24 K-4Y +2 K-12K +2 y)的DY
=∫(0,2)(6K - 2Y)DY
= 6...

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=∫(0,2)∫(2,4),K(6-XY)DXDY
=∫(0,2)(-KX ^ 2/2 +(6K-Y)×)[2.4] DY
=∫(0,2)(-16K / 2 +(6K-Y)4 +4 k/2-(6K-Y)2)DY
=∫(0,2),( - 8K +24 K-4Y +2 K-12K +2 y)的DY
=∫(0,2)(6K - 2Y)DY
= 6ky-Y ^ 2 [0,2] = 12K -4-0-0
= 12K-4

12K-4 = 1
K = 1/3的

收起

设√x=u x=u^2 dx=2udu
上式可转化为
∫1/(√x+1)dx=∫2udu/(u+1)=2∫udu/(1+u)=2[1+u-ln(1+u)]+C=2[1+√x-ln[(1+√x)]+C