先化简在求值:(-1/3XY)²×[xy(2x-y)-2x(xy-y)²],其中X=-3/2,Y=-2.
问题描述:
先化简在求值:(-1/3XY)²×[xy(2x-y)-2x(xy-y)²],其中X=-3/2,Y=-2.
答
先化简在求值
(-1/3XY)²×[xy(2x-y)-2x(xy-y)²],
=1/9x²y²*(2x²y-xy²-2x²y+2xy²)
=1/9x²y²*xy²
=1/9x³y^4
=1/9x(-3/2)³x(-2)^4
=-1/9x27/8x16
=-6