不定积分 x^2/x^2-3x+2 dx

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不定积分 x^2/x^2-3x+2 dx
不定积分 x^2/x^2-3x+2 dx

不定积分 x^2/x^2-3x+2 dx
原式=不定积分(x^2)/(x^2-3x+2)dx
=不定积分(x^2-3x+2+3x-2)/(x^2-3x+2)dx
=不定积分1dx+不定积分[3(x-1)+1]/(x-2)(x-1)dx
=x+不定积分3/(x-2)dx+不定积分1/(x-2)(x-1)dx
=x+3ln(x-2)+ln[(x-2)/(x-1)]+C
=x+ln[(x-2)^4/(x-1)]+C

∫ x^2/(x^2-3x+2) dx
=∫ [1 + (3x-2)/(x^2-3x+2) ]dx
=x + (3/2)∫dln(x^2-3x+2) + (5/2)∫ 1/(x^2-3x+2) dx
=x + (3/2)ln|x^2-3x+2| + (5/2)∫ 1/(x^2-3x+2) dx
=x + (3/2)ln|x^2-3x+2| + (5/2)∫ [1/(x-2) - 1/(x-1)] dx
=x + (3/2)ln|x^2-3x+2| + (5/2)ln|(x-2)/(x-1)| + C

你好:
x^2/(x^2-3x+2)=2x/x-2 - x/x-1
分成两部分分别作积分:
2x/x-2 根据牛顿莱布尼兹公式 得:2x ln(x-2)-2(x-2)ln(x-2)-ln(x-2)
=2(x-1)ln(x-2) - 2(x-2)
同理:x/x-1积分