先化简再求值(x-1/x-x-2/x+1)/(2x²-x/x²+2x+1)且x²-x-1 =0
问题描述:
先化简再求值(x-1/x-x-2/x+1)/(2x²-x/x²+2x+1)且x²-x-1 =0
答
你好 [(x-1)/x-(x-2)/(x+1)]/[(2x²-x)/(x²+2x+1)]={[(x-1)(x+1)-(x-2)x]/x(x+1)}/{x(2x-1)/(x+1)²}=(2x-1)/x(x+1)×(x+1)²/x(2x-1)=(x+1)/x²x²-x-1 ...