已知x^2=5,y^n=3,求(xy)^3n

已知x^n=5,y^n=3,求（xy）^2n的值 已知x^n=5,y^3,求（xy)^2n和(x^2y^3)^n的值 已知x^2=5,y^n=3,求(xy)^3n 】已知:【M】=-5x^2+3xy-2y^2,【N】=5x^2-6xy+2y^2.求：M-N、M+N、N-(M-N)】已知:【M】=-5x^2+3xy-2y^2,【N】=5x^2-6xy+2y^2求：M-N、M+N、N-(M-N) 已知xy^2=-2,求-xy（x^2y^5-xy^3-y)的值. 已知xy^2=-2 求-xy(x^2y^5-xy^3-y) 已知x的n次方 =5,y的n次方=3,求（xy）的2n次方 已知x^2-xy=5,xy-y^2=-3求3(x^2-xy)-xy+y^2 已知Y-x=3xy,求(5x+3xy-5y)÷(x-2xy-y) 已知xy/x+y=3,求代数式2x-5xy+2y/x-3xy+y 已知xy/x+y=2,求代数式3x-5xy+3y/-x+2xy-y的值 已知X+Y分之XY=2,求-X+3XY-Y分之3X+5XY+3Y 已知X-XY-2Y=0求2X+3XY-Y/X-2XY+5Y 已知xy=2(x+y),求(5x-xy+5y)/(3xy-x-y)的值 已知xy=2(x+y),求5x-xy+5y/3xy-x-y的值 已知x-y=3xy,求5x+2xy-5y/x-4xy-y的值 已知xy/x+y=2,求代数式8x-5xy+8y/-x+3xy-y的值 已知(x+2y+2m)(2x-y+n)=2x方＋3xy-2y方+5y-2,求m,n