先化简再求值:(X-Y)分之1-(X+Y)分之1)÷(X²+2XY+Y²)分之2y,其中x=√3+√2,y=√3-√2
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题目内容:
先化简再求值:(X-Y)分之1 -(X+Y)分之1)÷(X²+2XY+Y²)分之2y,其中x=√3+√2,y=√3-√2
优质解答
原式=(x+y-x+y)/(x+y)(x-y)÷2y/(x+y)²
=2y/(x+y)(x-y)*(x+y)²/2y
=(x+y)/(x-y)
=(√3+√2+√3-√2)/(√3+√2-√3+√2)
=2√3/2√2
=√6/2
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