(x+1)/(x²-2x+5)的不定积分怎么求
x+1= (1/2)(2x-2) +2
∫(x+1)/(x^2-2x+5) dx
=(1/2)∫(2x-1)/(x^2-2x+5) dx + 2∫dx/(x^2-2x+5)
=(1/2)ln|x^2-2x+5| + 2∫dx/(x^2-2x+5)
consider
x^2-2x+5 = (x-1)^2 +4
let
x-1= 2tany
dx= 2(secy)^2 dy
∫dx/(x^2-2x+5)
=(1/2)∫ dy
=(1/2)y + C'
=(1/2)arctan[(x-1)/2] + C'
∫(x+1)/(x^2-2x+5) dx
=(1/2)ln|x^2-2x+5| + 2∫dx/(x^2-2x+5)
=(1/2)ln|x^2-2x+5| + arctan[(x-1)/2] + C
扩展资料
常用积分公式:
1)∫0dx=c
2)∫x^udx=(x^(u+1))/(u+1)+c
3)∫1/xdx=ln|x|+c
4)∫a^xdx=(a^x)/lna+c
5)∫e^xdx=e^x+c
6)∫sinxdx=-cosx+c
7)∫cosxdx=sinx+c
8)∫1/(cosx)^2dx=tanx+c
9)∫1/(sinx)^2dx=-cotx+c
10)∫1/√(1-x^2) dx=arcsinx+c
2024-10-28 广告
∫(x+1)/(x^2-2x+5) dx
=(1/2)∫(2x-1)/(x^2-2x+5) dx + 2∫dx/(x^2-2x+5)
=(1/2)ln|x^2-2x+5| + 2∫dx/(x^2-2x+5)
consider
x^2-2x+5 = (x-1)^2 +4
let
x-1= 2tany
dx= 2(secy)^2 dy
∫dx/(x^2-2x+5)
=(1/2)∫ dy
=(1/2)y + C'
=(1/2)arctan[(x-1)/2] + C'
∫(x+1)/(x^2-2x+5) dx
=(1/2)ln|x^2-2x+5| + 2∫dx/(x^2-2x+5)
=(1/2)ln|x^2-2x+5| + arctan[(x-1)/2] + C