化简:(1)(a+2b)/(a+b)+2b的平方/a的平方-b的平方(2)(x的平方-1)/(x的平方+2x+1)-(x+1)/(x-1)

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化简:(1)(a+2b)/(a+b)+2b的平方/a的平方-b的平方(2)(x的平方-1)/(x的平方+2x+1)-(x+1)/(x-1)
化简:(1)(a+2b)/(a+b)+2b的平方/a的平方-b的平方
(2)(x的平方-1)/(x的平方+2x+1)-(x+1)/(x-1)

化简:(1)(a+2b)/(a+b)+2b的平方/a的平方-b的平方(2)(x的平方-1)/(x的平方+2x+1)-(x+1)/(x-1)
(1)(a+2b)/(a+b)+2b²/(a²-b²)
=(a+2b)(a-b)/(a²-b²)+2b²/(a²-b²)
=(a²+ab-2b²+2b²)/(a²-b²)
=a(a+b)/[(a+b)(a-b)]
=a/(a-b)
(2)(x²-1)/(x²+2x+1)-(x+1)/(x-1)
=(x+1)(x-1)/(x+1)²-(x+1)/(x-1)
=(x-1)/(x+1)-(x+1)/(x-1)
=(x²-2x+1-x²-2x-1)/(x+1)(x-1)
=-4x/(x+1)(x-1)

(a+2b)/(a+b)+2b的平方/a的平方-b的平方
=[(a+2b)(a-b)+2b²]/(a+b)(a-b)
=(a²+ab)/(a+b)(a-b)
=a/(a-b)