xy'''+2x^2*y'^2+x^3y=x^4+1是几阶微分方程

因式分解:12xy^2(y-x)+xy^3(x-y)+4x^2y(x-y) X^Y-2XY^2+y^3 化简：x-y/x+3y÷x^-y^2/x^2+6xy+9y^2-(xy/x+y) 1、(-7x^y)(2x^y-3xy^3+xy) 2、((x-y)^6)/((y-x)^3)/(x-y) 因式分解 x-xy+3y-3x 2x+xy-y-4x+5y-6 [x(x^2y^2-xy)-y(x^2-x^3y)]/(2x^2y) [x(x^2y^2-xy)-y(x^2-x^3y)]/3x^2y [x(x^2y^2-xy)-y(x^2-x^3y)]/3x^2y (-x-y)(x^2+xy+y^2) 化简x^-y^/x^-2xy+y^ 2*(x-y)²(y-x)(xy) -xy^2(x+y)^3+x(x+y)^2因式分解 (x+3y)/(x^2+xy)-x+y计算题 x*x+xy=3,xy+y*y=2,则x*x+2xy+y*y=________? （x^2+xy/x-y)/（xy/x-y)计算 (x-2xy)*(-xy+2y*y)-(3x*x-2xy)(x-9xy+6y*y)答案应为-2x-x*x-3x， x^2-xy-6y^2+3xy+y+2 (x+y)(x-y)-(2xy+3y)平方平方是(2xy+3y)的