先化简,再求值：[（5X+2Y)(3X+2Y)+(X-2Y)(X+2Y)]/4X,其中X=2,Y=-3_数学解答

先化简,再求值：[（5X+2Y)(3X+2Y)+(X-2Y)(X+2Y)]/4X,其中X=2,Y=-3

人气：157 ℃　时间：2019-08-18 03:49:10

解答

[（5X+2Y)(3X+2Y)+(X-2Y)(X+2Y)]/4X
=[15x²+10xy+6xy+4y²+x²-4y²]/4x
=[16x²+16xy]/4x
=4x+4y
=4(x+y)
=4*(2-3)
=-4