求积分∫(x^7-4x^5-x^3+5x+1)/(x^5-2x^4-x+2)dx的具体解答过程

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求积分∫(x^7-4x^5-x^3+5x+1)/(x^5-2x^4-x+2)dx的具体解答过程

求积分∫(x^7-4x^5-x^3+5x+1)/(x^5-2x^4-x+2)dx的具体解答过程
求积分∫(x^7-4x^5-x^3+5x+1)/(x^5-2x^4-x+2)dx的具体解答过程

求积分∫(x^7-4x^5-x^3+5x+1)/(x^5-2x^4-x+2)dx的具体解答过程
有理分式求积分的通用解法:
(1)化为真分式和一个多项式的和.
(2)将真分式分解为若干个一次和二次真分式的和.
(3)分别求各项积分.

∫ (x^7-4x^5-x^3+5x+1)/(x^5-2x^4-x+2) dx
= ∫ [ (x^2+2x) + (1+x)/(x^5-2x^4-x+2) ] dx
= ∫ [ (x^2+2x) + 1/[(x^2+1)(x-1)(x-2)] ] dx
= ∫ [ (x^2+2x) + 1/10 * [ (3x+1)/(x^2+1) - 5/(x-1) + 2/(x-2)] ] dx
= x^3/3 +x^2 + 1/10 * [ 3/2 * ln(1+x^2) + arctan(x) - 5ln|x-1| + 2ln|x-2| ] + C

一天很愉快名扬花鼓没开通过

∫(x7-4x5-x3+5x+1)/ (x5-2x4-x+2)dx=

∫[x3(x4-1)-4x(x4-1) +(x+1)]/(x-2)(x4-1)dx=∫x3(x4-1)/(x-2)(x4-1)dx-∫4x(x4-1)/(x-2)(x4-1)dx+∫(x+1)/ (x-2)(x2+1)(x+1)(x-1)dx=∫x3/(x-2)dx-∫4x/(x-2)dx+∫1/(x-2)(x2+1)(x-1)dx=∫(x3-2x2+2x2)/(x-2) dx-∫(4x-8+8)/(x-2)dx-∫1/(x-2)(x2+1)(x-1)dx

剩下的是基本积分 我就不做了