先化简在求值﹙1/X+Y+1/X-Y﹚÷2XY/X-Y,其中X=√3+√2,Y=﹣√2

问题描述:

先化简在求值﹙1/X+Y+1/X-Y﹚÷2XY/X-Y,其中X=√3+√2,Y=﹣√2

原式=(1/(x+y)+1/(x-y))÷2xy/(x-y) =2x/( x-y)÷2xy/(x-y) =1/y =-2/√2