Question

化简求值(-2x+3y)^2+(-2x+3y)^2(-2x-3y)^2-(x-y)^2,其中x=-2,y=1/2

Answer 1

化简求值(-2x+3y)²+(-2x+3y)²(-2x-3y)²-(x-y)²；其中x=-2，y=1/2。
解：原式=(2x-3y)²+(2x-3y)²(2x+3y)²-(x-y)²=(2x-3y)²+(4x²-9y²)²-(x-y)²
=(-4-3/2)²+(16-9/4)²-(-2-1/2)²=121/4+3025/16-25/4=(484+3025-100)/16=3409/16

Answer 2

(-2x+3y)^2+(-2x+3y)^2(-2x-3y)^2-(x-y)^2
=4x²-12xy+9y²+(4x²-9y²)²-x²+2xy-y²
=3x²-10xy+8y²+(4x²-9y²)²
=12+10+2+(16-9/4)²
=24+3025/16
=213又16分之1
如果题目没打错,就是这样了