6xy-3[3y²-(x²-2xy)+1],其中x=-2,y=-1/3化简求值要过程
6xy-3[3y²-(x²-2xy)+1],其中x=-2,y=-1/3化简求值要过程
已知 (x+1)² +|y-1|=0,求 2(xy-xy²)-(3xy²-xy) 的值.
先化简,再求值∶(1/x-y-1/x+y)÷2y/x²+2xy+y²,其中x=根号下3加根号下2,y
3y/2x+2y+2xy/x²+xy 2x/x²-64y²-1/x-8y (1/a+1/b
①先化简,再求值.4(3x²y—1/2xy²)—5(—xy²+3x²y),其中x
(3x+2y)(9x²-6xy+4y²﹚
化简(x²-2xy+y²-1)/x-y-1=? 写上过程! 谢!
问已知x²+y²=7,xy=-2,求5x²-3xy-4y²-11xy-7x&su
先化简,再求值:3xy²(-x²y+2x³y²)-4xy(-xy²)·
计算:(1).(-2xy²)*(3x²y)²
化简、求值(1)化简:3(x-2y)+2(3x+y)(2)先化简再求值(3x²y-2xy²)-(xy
分解因式:x²-3xy+2y²+x-2