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∫(x+1)/x^2-2x+2dx等于什么

题目详情
∫(x+1)/x^2-2x+2dx等于什么
▼优质解答
答案和解析
∫ (x+1)/(x²-2x+2) dx
= ∫ [(1/2)(2x-2)+2]/(x²-2x+2) dx
= (1/2)∫ (2x-2)/(x²-2x+2) dx + ∫ 2/(x²-2x+2) dx
= (1/2)∫ d(x²-2x+2)/(x²-2x+2) + 2∫ 1/[(x-1)²+1] d(x-1)
= (1/2)ln| x²-2x+2 | + 2arctan(x-1) + C
Note:
Let x+1 = A(2x-2)+B
x+1 = 2Ax + (B-2A)
2A=1 => A=1/2
B-2A=1 => B=1+2(1/2)=2
∴x+1 = (1/2)(2x-2)+2