4-( 12x- y) 9(x- y)的平方-搜答案-大师作文网

6*(x+y)^7-9*(x+y)^3*(x-y)^2*((3*x-3*y)*(x+y))^(1/2)ok?再问：可不可以写清楚点

x(x-y)+4(y-x)=x(x-y)-4(x-y)=(x-y)(x-4)=(x-y)(X+2)(X-2)

2x-y/x+3y=2得x+3y/2x-y=1/24x-2y/x+3y减4x+12y除以2x-y=2(2x-y)/x+3y-4(x+3y)/2x-y=2乘以2-4乖以1/2=4-2=2

4-12(x-y)+9(x+y)^2

4-12(x-y)+9(x+y)^2=[3(x+y)]^2-12xy+2^2=[3(x+y)-2]^2=(3x+3y-2)^2

9(x-y)^2+12(x^2-y^2)+4(x+y)^2=[3(x-y)]^2+2*3(x-y)*2(x+y)+[2(x+y)]^2=[3(x-y)+2(x+y)]^2=(5x-y)^2

(x^2-y^2)/(x+y)-(4x(x-y)+y^2)/(2x-y)=(x-y)(x+y)/(x+y)-(4x^2-4xy+y^2)/(2x-y)=(x-y)-(2x-y)^2/(2x-y)=(x

答案是2.4x-2y/x+3y=(2x-y/x+3y)乘以2=4,4x+12y/2x-y=(x+3y/2x-y)乘以4=1/2x4=2,所以代数式等于4-2=2.

∵x²+y²-4x+2y+5=0x²-4x+4+y²+2y+1=0(x-2)²+(y+1)²=0x-2=0y+1=0∴x=2y=-14x&#

4-12(x-y)+9(x-y)²=[2－3﹙x－y﹚]²=﹙2－3x＋3y﹚²再问：那个小的2是怎么弄的再答：二次方，就是平方

(x+y)-(2x+y/2)-(3x+y/6)-(4x+y/12)-(5x+y/20)-……-(10x+y/90)=x-2x-3x-4x-..-10x+y*(1-1/2-1/6-1/12-..1/90

什么意思?求什么?再问：化简后代入求值再答：4x³y+12x²y²+9xy³/4x³-9xy²=(2x²+3xy)(2xy+3y&

[12(x+y)³(y-x)]³÷[4(x+y)²（x-y)]²=【12×12×12÷(4×4)(x+y)^9(y-x)^3】÷【(x+y)^4(x-y)^2】

这是完全平方原式=[3(x-y)]²+2×[3(x-y)]×2+2²=[3(x-y)+2]²=(3x-3y+2)²

{(x,y) |x|+|y|

区域是一个正方形

4x=9yx=9/4*y(1)(x+y)/y=[(9/4)y+y]/y=(9/4+1)y/y=9/4+1=13/4(2)(y-x)/2x=[y-(9/4)y]/[2*(9/4)y]=(1-9/4)y/

解9y=3x-(x-1)2x-9y+1=0①4(x+y)-(2x+4)=8y2x-4y-4=0②②-①得：5y-5=0∴y=1将y=1代入①得：2x-9+1=0∴x=4∴方程的解为：x=4,y=1

完整设1/(x+y)=a,1/(x-y)=b原方程组可变为4a+6b=39b-a=1a=9b-136b-4+6b=3b=1/6,a=1/2x+y=2x-y=6所以原方程组的解为：x=4,y=-2

3y=2x,两边同时乘以1/3x可得y/x=2/3;y/3=x/2,两边同时乘以3/x可得y/x=3/2;12/x=9y,两边都乘以x/9可得x/y=4/3.

x>y?x:y

判断X的数值是否大于Y的数值如果是则为真等式去X的值反之取Y的值