把(x+3y)(3x-4y)-(x-2y)(x+3y)分解因式!答案是2(x+3y)(x-y) 我想问.上面的2个(x+3y)不是可以变成(x+3y)²为什么最后会变成(x+3y)的?指教指教下!

(x-y) (x-2y)+(x+2y) (x-3y)-2(x-3y) (x-4y)= 把(x-y)看作一个整体,化解:5(x-y)+2(x-y)-4(x-y)= 3(x-y)把(x-y)看作一个整体,化解:5(x-y)+2(x-y)-4(x-y)=3(x-y)²-4(x-y)+7(x-y)-6(x-y)²= 把x-y看做一个整体,合并同类项. 3(y-x)^2+2(x-y)+(y-x)-(x-y)^2 把x-y看作一个整体,合并同类项3(y-x)+2(x-y)+(y-x)-(x-y)谢谢了, (x+3y-4)(2x-y) 计算（2x-3y)(x+4y)-(3x+y)(x-2y)（2x-3y)(x+4y)-(3x+y)(x-2y) 因式分解(x-2y)(x-3y)+(x-4y)(x-5y)+（x-3y)(x-5y)+(x-2y)(x-4y) x²/xy-x/y 3x/4x+y - x-2y/4x+y (1-y/y+x)÷x/y²-x² x(x-y)2-(y-x)3 把(x-y)看作一个整体,化简:(1)5(x-y)+2(x-y)-4(x-y);(2)3(x-y²-4(x-y)+7（x-y)-6(x-y) 把(x-y)看做一个整体,合并同类项5(x-y)+2(x-y)-4(x-y)=3(x-y)次方-4(x-y)+7(x-y)-6(x-y)次方= （y-x)+x(x-y)^3-(y-x)^4 因式分解 (2x+y)(2x-3y)+x(2y+y) 2a(x-y)-4b(x-y) [2/3x-2/x+y(x+y/3x-x-y)]/x-y/x 化简：{2/3x-2/(x+y)[(x+y)/3x-x-y]}/(x+y)/x 计算2/3x-2/x+y(x+y/3x-x-y)/x-y/x 化简3x-2/(x+y)[(x+y)/3x-x-y]÷(x-y)/x 大家帮帮我把（-2y²）³+y乘y的5次方 3x（3y-x)-（4x-3y）（x+3y)