化简：3ab^2/2x^3y×(-8xy/9a^2b)÷(3x/-4b)

化简：3x^2-[5xy-(x^y-3xy)+4x^2y-8xy] 化简：4ab+8-2b²-9ab-6= (2)先化简,再求值：3x²y-[2x²y-3(2xy-x²y)-xy]其中x=-1,y=-2 化简：x-y/x+3y÷x^-y^2/x^2+6xy+9y^2-(xy/x+y) 化简2(x²y+xy)-3(x²y-xy)-4x²y 化简(3x^2-5xy)+{-x^2-[-3xy+2(x^2-xy)+y^2]} 化简：3ab^2/2x^3y×(-8xy/9a^2b)÷(3x/-4b) 化简：2x²y+{2xy-[3x²y-2(-3x²y+2xy)]-4xy}化简：2x²y+{2xy-[3x²y-2(-3x²y+2xy)]-4xy} 2x²y-3(2xy-xy)-xy 化简3x^2y-[2xy^2-2（xy-3/2x^2y）+xy]+3xy^2 化简!1、（x^2-xy）+xy+y^2 2、3（x^2-xy）-xy+y^2 5x^2y-3xy^2+4xy-14xy^2+4xy-2x^2y（化简） 已知xy/x+y=2,求代数式8x-5xy+8y/-x+3xy-y的值 诺x+y=6,xy=4 求(5x-4y-3xy)-(8x-y+2xy) 8x^2y+6xy^2和5a^2b^3-3ab 因式分解 因式分解30题(要过程)am+an+bm+bn x^2+5y-xy-5x x2+xy+2xz+x (a+b)x-(b+a)y -12x(x-y)-(y-x)x^2 2x^2+4x+2 x(x+z)-y(y+z) 2(x^2-3ab)+x(4a-3b) 4x^2+12xy+9y^2-25 x^4-16 16x^4-1 x^2+9x+8 x^2-10xy+24y^2 2x^2+15xy-8y^2 3x^2-6xy+3y^2 24x^2+22x-21 -x^2+4xy- 把下列各式分解因式:x^2-7x+10 x^2+2xy-24y^2 ab^2-7ab+12a 2x^2-7x+3 6x^2-7x-5 5x^2+6xy-8y^2 急x^2-7x+10 x^2+2xy-24y^2 ab^2-7ab+12a 2x^2-7x+3 6x^2-7x-5 5x^2+6xy-8y^2 已知多项式2x^2+3xy-2y^2-x+8y-6的值恒等于2x^2+3xy-2y^2+A(2x-y)+B(x+2y)+AB,求A+B的值. 已知多项式2x^2-2y^2+3xy-x+8y-6的值恒等于2x^2+3xy-2y^2+A(2x-y)+B(x+2y)+AB.求A+B的值?