3x乘以4y怎么算-搜答案-拍题作业网

3x*(4x*x-9)*(2x-3)=(12x的三次方-27x)*(2x-3)=24x的四次方-54x的平方-36x的三次方+81x

由于根号下必须是大于等于零,则有：x-3>=0.3-x>=0得x>=3.x

124²-123*125=124²-(124-1)(124+1)=124²-124²+1=1(x+2y)²-(x+y)(3x-y)-5y²=

干什么?计算吗?(3x-2y)²×(3x+2y)²×(9x²+4y²)²=[(3x-2y)(3x+2y)]²×(9x²+4y

(x-y)^3乘以（y-x）^2=(x-y)^3*(x-y)^2=(x-y)^(3+2)=(x-y)^5A

(y-x)(x-y)^3(y-x)^5=(y-x)[-(y-x)^3](y-x)^5=-(y-x)^(1+3+5)=-(y-x)^9=(x-y)^9

说明一下：“*”是乘号15*（3x-8）-4*（2x+3）=6*（4x-4）-4首先,化简,得（15*3x-15*8）-（4*2x+4*3）=6*4x-6*4-4去括号（记的变号）,得45x-120-

(8x^2/9y^2)*(3y/-4x)=-2x/3y不懂请追问,满意请采纳~再问：过程？？？？再答：就相当于（8x的平方除以-4x）乘以(3y除以9y的平方）=-2x乘以3y分之一=负的3y分之2x

(x+y的2n-1次方)乘以(-x-y的6次方)+(x+y的n+3次方)乘以(x+y的n+2次方)=(x+y)^(2n-1)×(x+y)^6+(x+y)^(n+3)×(x+y)^(n+2)=(x+y)

(-2y/x的平方)的平方乘以(-x/y)除以(2/xy)的四次方=4y²/x^4*(-x/y)÷(2/xy)^4=-4y/x³*(xy)^4÷16=-y的五次方/4x

原式=-（x+y)²×（x-y)²=-（x²-y²）²

(x/x+y+2y/x+y)乘以xy/x+2y除以(1/x+1/y)=(x+2y)/(x+y)*xy/(x+2y)/[(x+y)/(xy)]=xy/(x+y)*xy/(x+y)=(xy)^2/(x+y

xy³+xy²+xy=xy(y²+y+1)

这是个平方差-(x-y+1)(x-y-1)=-[x^2-(y-1)^2]=(y-1)^2-x^2=y^2-2y+1-x^2再问：如何去掉负号这是因式分解得来的再答：噢乘进去就行了-(x-y+1)(x-

(x-y)^2(x-y)^3*(y-x)^2*(y-x)^3=-(x-y)^2(x-y)^3*(x-y)^2*(x-y)^3=-(x-y)^10

-(y-x)4次方

可以用plot函数或ezplot函数绘制.symsx;y=1-cos(3*x)*exp(-x);ezplot(x,y);或x=0:0.0001:4;y=1-cos(3*x).*exp(-x);plot

x九次方y

（x+2y）的平方再问：不对再答：(x-2y)的平方再问：再答：再问：谢谢了再答：不谢，>3