已知x2-1分之2x=x+1分之A+(x-1分之B),求A,B的值抱歉,题目应该是2x/X²-4=A/(x+2)+B/(x-2),求A,B的值

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已知x2-1分之2x=x+1分之A+(x-1分之B),求A,B的值
抱歉,题目应该是2x/X²-4=A/(x+2)+B/(x-2),求A,B的值

A/(x+1)+B/(x-1)=(2x+3)/(x²-1)[(x-1)A+(x+1)B]/(x²-1)=(2x+3)/(x²-1)[Ax-A+Bx+B]/(x²-1)=(2x+3)/(x²-1)[x(A+B)+(B-A)]/(x²-1)=(2x+3)/(x²-1)x(A+B)+(B-A)=(2x+3)要使等式两边相等dg则必有如下等式:A+B=2B-A=3两式相加19B=5/2=2.5A=2.5-3=-0.5

你的题目应该是:2x/(x^2-1) = A/(x+1) + B/(x-1)对问题进行变形得:2x/[(x+1)(x-1)] = A/(x+1) + B/(x-1)对等式的右边进行通分整理得 2x/[(x+1)(x-1)] = [(A+B)x + (B-A)]/[(x+1)(x-1)]要使等式成立,左右的分母应相...