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
问题描述：
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
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