先化简再求值:2(x²y+xy)-3(x²y-xy)-4x²y 其中x=-1,y=1先化简再求值:2(x²y+xy)-3(x²y-xy)-4x²y 其中x=-1,y=1
来源:学生作业帮助网 编辑:六六作业网 时间:2024/12/19 17:24:19
先化简再求值:2(x²y+xy)-3(x²y-xy)-4x²y其中x=-1,y=1先化简再求值:2(x²y+xy)-3(x²y-xy)-4x²
先化简再求值:2(x²y+xy)-3(x²y-xy)-4x²y 其中x=-1,y=1先化简再求值:2(x²y+xy)-3(x²y-xy)-4x²y 其中x=-1,y=1
先化简再求值:2(x²y+xy)-3(x²y-xy)-4x²y 其中x=-1,y=1
先化简再求值:
2(x²y+xy)-3(x²y-xy)-4x²y
其中x=-1,y=1
先化简再求值:2(x²y+xy)-3(x²y-xy)-4x²y 其中x=-1,y=1先化简再求值:2(x²y+xy)-3(x²y-xy)-4x²y 其中x=-1,y=1
=-5x^2*y+5xy
=5xy(1-x)=-10
2(x²y+xy)-3(x²y-xy)-4x²y
=2x²y+2xy-3x²y+3xy-4x²y
=-5x²y+5xy
=-5xy(x-1)
=-5*(-1)*1*(-1-1)
=5*(-2)
=-10
不懂可追问,有帮助请采纳,谢谢!