求5x²y-[2x²y-﹙3xy-xy²﹚-3x²]-2xy²-y²的值
∵(x+y)³+|x-y+10|=0
∴x+y=0,x-y+10≥0
∴x=-5,y=5
∴5x²y-[2x²y-﹙3xy-xy²﹚-3x²]-2xy²-y²
=5x²y-﹙2x²y-3xy+xy²-3x²﹚-2xy²-y²
=5x²y-2x²y+3xy-xy²+3x²-2xy²-y²
=3x²y+3xy-3xy²+3x²-y²
=3xy(x+y+1)+3x²-y²
x=-5,y=5代入
=3·-5·5(-5+5+1)+3·25-25
=-25
希望满意采纳。
∴x+y=0,x-y+10≥0
∴x=-5,y=5
∴5x²y-[2x²y-﹙3xy-xy²﹚-3x²]-2xy²-y²
=5x²y-﹙2x²y-3xy+xy²-3x²﹚-2xy²-y²
=5x²y-2x²y+3xy-xy²+3x²-2xy²-y²
=3x²y+3xy-3xy²+3x²-y²
=3xy(x+y+1)+3x²-y²
x=-5,y=5代入
=3·-5·5(-5+5+1)+3·25-25
=-25
希望满意采纳。
温馨提示:答案为网友推荐,仅供参考