先化简,再求值,先化简,再求值,【1/(x-y)】-【1/(x+y)】/【xy²/(x²-y²)】,其中x=√2+1,y=√2-1

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先化简,再求值,先化简,再求值,【1/(x-y)】-【1/(x+y)】/【xy²/(x²-y²)】,其中x=√2+1,y=√2-1
先化简,再求值,
先化简,再求值,【1/(x-y)】-【1/(x+y)】/【xy²/(x²-y²)】,其中x=√2+1,
y=√2-1

先化简,再求值,先化简,再求值,【1/(x-y)】-【1/(x+y)】/【xy²/(x²-y²)】,其中x=√2+1,y=√2-1
先化简,再求值:【1/(x-y)】-【1/(x+y)】/【xy²/(x²-y²)】,其中x=√2+1,
y=√2-1
【1/(x-y)】-【1/(x+y)】/【xy²/(x²-y²)】
=(x+y-x+y)/(x^2-y^2)*(x^2-y^2)/(xy^2)
=2y/(xy^2)
=2/(xy)
=2/(√2+1)(√2-1)
=2 .

〔(5/(a-2))-a-2〕=(3 a)(3-a)/(a-2) 消除同类项可知 原式等于 (-1)/2(3 a)=(-1)/2√3=-√3/6 望采纳 〔(a-3