先化简,再求值:x 的三次方 2x的平方 x分之x的平方 2x-8
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原式=x³-2x²-5x-4x³-4x²+6x-1=(x³-4x³)+(-2x²-4x²)+(-5x+6x)-1=-3x
{(x的三次方-x)分之(x的平方-2x+1)}*(1-x分之1)=【(x-1)^2/[x(x+1)(x-1)]】*(x-1)/x=[(x-1)/[x(x+1)]]*(x-1)/x=(x-1)^2/[
X(2X+1)(2X-3)再问:过程再答:看错了以为是-3。=2x³+4x-x²-x-3x²+2x³=4X³-4X²+3X=X(4X
(2x-y)的十三次方除以【(2x-y)的三次方】的二次方除以【(y-2x)的二次方】的三次方=(2x-y)的十三次方除以(2x-y)的6次方】除以(2x-y)的6次方=(2x-y)的7次方除以(2x
4x的三次方(-y的三次方)的平方-3x(—x)的平方(-y的平方)的三次方,x=-1,y=-2,=4x^3(-y^3)^2-3x(—x)^2(-y^2)^3=4x^3*(y^6)-3x*x^2(-y
化简得(16a²+64a-27/64aX²)/X²将数字带入得答案为261/128
(x-2y)(x方+2xy+4y方)-x(x-y)(x+y)+(2y)的三次方=x³-(2y)³-x(x²-y²)+(2y)³=x³-x
x^2(x^2-x+1)-x(x^3-x^2+x-1)=x^2(x^2-x+1)-x^2(x^2-x+1)+x=x=1/2
3x三次方2x二次方-{5x-2-[6-2x-(-x二次方+3x三次方)]=6X^5-[5X-2-6+2X+(-X^2+3X^3)]=6X^5-(7X-8-X^2+3X^3)=6X^5-3X^3+X^
2(x的三次方-2y的平方)-(x-2y)-(x-3y的平方+2x的三次方)其中x=-3,y=-2=2x³-4y²-x+2y-x+3y²-2x³=-2x+2y-
解3(x-1)³y-(1-x)³z=3(x-1)³y+(x-1)³z=(x-1)³(3y+z)=(1/2-1)³(3×1/5+6/5)=-1
2x+1=02x=-1x=-1/2(3x的四次方-2x的三次方)/(-x)-(x-x的平方)*3x=-3x³+2x²-3x²+3x³=-x²=-(-1
[1/(x-3)]×[(x³-6x²+9x)/(x²-2x)]-[(1-x)/(2-x)]=1/(x-3)*x*(x-3)²/[x(x-2)]-(1-x)/(2
81^3=3^(4*3)27^3=3^(3*4)所以81^3*27^3=(3^12)^2=9^12所以x=9
如果题目是[(x³-x²)/(x+1)]/{[(2x-2)/(x+1)]-(x-1)},那么原式=[x²(x-1)/(x+1)]/{[(2x-2)-(x-1)(x+1)]
=x²(x-1)/x(x-1)-(1+x)(1-x)/(x+1)=x-(1-x)=2x-1当x=2时原式=4-1=3
17x的9次方,上式为2x的9次方-64x的9次方+81x的9次方
原式=(x+1)/(x²+1)×(x²+1)(x²-1)/(x+1)³-(x-3)/(x+1)=(x²-1)/(x+1)²-(x-3)/(x
(x的平方+3x的平方+2)-(-1+3x的三次方+2x的二次方)=x²+3x²+2+1-3x³-2x²=-3x³+2x²+3当x=2时原式