（7y-2x)-(7x-4y)

计算(x^8-x^7y+x^5y^3-x^4y^4+x^3y^5-x^y^7+y^8)(x^2+xy+y^2)计算(x^8-x^7y+x^5y^3-x^4y^4+x^3y^5-x^y^7+y^8)(x

把(x+y),(x-y)个作为一个整体合并同类项1,7(x+y)-2(x+y)-4(x+y)+2(x+y)2,(x-y)²＋2(x-y)－(x-y)－2(x-y)²把(x+y),(

(x-y)(x-2y)+(x-2y)(x-7y),其中X=4,Y=1.5(x-y)(x-2y)+(x-2y)(x-7y),其中X=4,Y=1.5(x-y)(x-2y)+(x-2y)(x-7y),其中X

计算:1/(x-y)-1/(x+y)-2y/(x^2+y^2)-4y^3/(x^4+y^4)-8x^7/(x^8+y^8)计算:1/(x-y)-1/(x+y)-2y/(x^2+y^2)-4y^3/(x

化简3(x-y)-7(x--y)+2(y-x)化简3(x-y)-7(x--y)+2(y-x)化简3(x-y)-7(x--y)+2(y-x)原式=3x-3y-(7x-7y)+(2y-2x)=3x-3y-

先化简再求值{(x-y)(x+y)-(x+y)(x-2y)}/y其中xy的值是代数式{(3x-2y-7)^2+|2x+3y先化简再求值{(x-y)(x+y)-(x+y)(x-2y)}/y其中x和y的值

7x:4y,x:y=():(7x:4y,x:y=():(7x:4y,x:y=():(=4：7你的问法有问题，他们回答的也太省略了。你的意思是：7x=4y，那么x:y=?对吧我告诉你具体做法：比例就是除

化简2（2X-7Y)(7Y+2X)+X^2-(-4X+5Y)(-5Y-4X)化简2（2X-7Y)(7Y+2X)+X^2-(-4X+5Y)(-5Y-4X)化简2（2X-7Y)(7Y+2X)+X^2-(-

已知（x+y）2=2,(x-y)3=3,求(x+y)7(x-y)2(x+y)3(y-x)4的值已知（x+y）2=2,(x-y)3=3,求(x+y)7(x-y)2(x+y)3(y-x)4的值已知（x+y

已知实数x.y满足根号(x+y-8)+根号(8-x-y)=根号(3x-y-4)+根号(x-2y+7),求x,y已知实数x.y满足根号(x+y-8)+根号(8-x-y)=根号(3x-y-4)+根号(x-

将(x-y)看成一个整体,将3(x-y)²-4(x-y)+7(x-y)-6(y-x)²-2(y-x)合并同类项.将(x-y)看成一个整体,将3(x-y)²-4(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)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

x-4y分之3x+4y-x分之x+y-x*x-4y分之7yx-4y分之3x+4y-x分之x+y-x*x-4y分之7yx-4y分之3x+4y-x分之x+y-x*x-4y分之7yx-4y分之3x+4y-x

（7y-2x）-（7x-4y)（7y-2x）-（7x-4y)（7y-2x）-（7x-4y)（7y-2x）-（7x-4y)=7y-2x-7x+4y=-9x+11y（7y-2x)-(7x-4y)=7y-2

(7y-2x)-(7x-4y)(7y-2x)-(7x-4y)(7y-2x)-(7x-4y)11y-9x(7y-2x)-(7x-4y)=-9x+11y如果不懂，请追问，祝学习愉快！

因式分解x^8-7x^4y^2+y^4因式分解x^8-7x^4y^2+y^4因式分解x^8-7x^4y^2+y^4x^8-7x^4y^2+y^4=x^8+2x^4y^2+y^4-9x^4y^2=(x^

[(x+2y)²-(x+y)(x-y)-7y²】÷（2y）[(x+2y)²-(x+y)(x-y)-7y²】÷（2y）[(x+2y)²-(x+y)(x-

5(2x-7y)-(4x-10y)全过程5(2x-7y)-(4x-10y)全过程5(2x-7y)-(4x-10y)全过程10x-35y-4x+10y

（4x-7y)-(3x+2y)（4x-7y)-(3x+2y)（4x-7y)-(3x+2y)原式=4x-7y-3x-2y=(4x-3x)-(7y+2y)=x-9y合并同类项

(2x-7y)(3x+4y-1)(2x-7y)(3x+4y-1)(2x-7y)(3x+4y-1)2.5