先化简,再求值.(x-1)/(x-2)·(x²-4)/(x²-2x+1)÷1/(x²-1),其中x²-x=10

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先化简,再求值.(x-1)/(x-2)·(x²-4)/(x²-2x+1)÷1/(x²-1),其中x²-x=10

先化简,再求值.(x-1)/(x-2)·(x²-4)/(x²-2x+1)÷1/(x²-1),其中x²-x=10
先化简,再求值.(x-1)/(x-2)·(x²-4)/(x²-2x+1)÷1/(x²-1),其中x²-x=10

先化简,再求值.(x-1)/(x-2)·(x²-4)/(x²-2x+1)÷1/(x²-1),其中x²-x=10
(x-1)/(x-2) ·(x²-4)/(x²-2x+1)÷1/(x²-1)
=(x-1)/(x-2) · (x-2)(x+2)/(x-1)² ÷ 1/(x-1)(x+1)
=(x+2)/(x-1) ÷ 1/(x-1)(x+1)
=(x+2)(x+1)
=x²+3x+2
∵ x² - x =10,配方得:
( x-1/2)²=10+1/4
解得:x=(√41+1)/2,或 x=(√41-1)/2
代入上式,得:
① 当 x=(√41+1)/2 时,
[(√41+1)/2]²+3×(√41+1)/2+2=14+2√41;
② 当 x=(√41-1)/2 时,
[(√41-1)/2]²+3×(√41-1)/2+2=11+√41.
.不懂的地方追问吧