计算 x² 2x分之x² 4x 4

要过程还是答案再问：都要再答：x2+x-2=2{x+x-1}=2a再答：第二题原理一样的再答：懂了吗？再问：我打错题了……再答：？再答：什么意思？再问：-1次再问：指数错了再答：重新打一遍再问：已知，

原式=[(2x-6)/(x^2-4x+4)]/(x+3)*(x^2+x-6)/(3-x)=[2(x-3)/(x-2)^2]/(x+3)*(x+3)(x-2)/(3-x)=-2/(x-2)

用简便方法计算：2^4x4^5x（-0.125）^4=(2*4*0.125)^4*4=1^4*4=4

1－x分之1＋1＋x分之1＋1＋x²分之2＋1＋x4次方分之4=1－x²分之（x+1+1-x)＋1+x²分之2＋1＋x4次方分之4=1－x²分之1＋1+x

3x+20-25=x-403x-x=25-20-402x=-35x=-17.5

原式=(x^2+3x)/(x^2+x-6)-(x+2)/(x^2-4)=x(x+3)/(x+3)*(x-2)-(x+2)/(x+2)*(x-2)=x/(x-2)-1/(x-2)=(x-1)/(x-2)

(x^2-2x分之x+2-x^2-4x+4分之x-1)/x分之4-x=[(x+2)/(x(x-2)-(x-1)(x-2)^2]/(4-x)/x=[(x+2)(x-2)-x(x-1)/x(x-2)^2]

=[(x+2)/x(x-2)-(x-1)/(x-2)²]×(x-4)/x=[(x-2)(x+2)-x(x-1)]/x(x-2)²×(x-4)/x=(x-4)/x(x-2)²

其实第n项=n*(n+1)=n^+n;则前n项的和为n(n+1)(2n+1)/6+n(n+1)/2=n(n+1)(n+2)/3.题目：带入即可得2010/3

(x+2)/(x²-2x)-(x-1)/(x²-4x+4)=(x+2)/[x(x-2)]-(x-1)/(x-2)²=[(x+2)(x-2)-x(x-1)]/[x(x-2)

X+（X+12)x5分之4=42X+0.8X+9.6=421.8X=32.4X=18X+（X+28）x4分之3=42X+0.75X+21=421.75X=63X=36X+(15+X)x5分之2=69X

[(x-2)分之3x-2分之x]×x分之(x²-4)=[2(x-2)分之6x-2(x-2)分之(x²-2x)]×x分之[(x+2)(x-2)]=2(x-2)分之(4x-x²

原式=2x/(x^2-4)-1/(2-x)+3/(x+2)=2x/(x-2)(x+2)+1/(x-2)+3/(x+2)=[2x+(x+2)+3(x-2)]/(x-2)(x+2)=(6x-4)/(x-2

啥意思

解原式=3(2-x)/3(x-4)(x+2)+(x+4)(x-4)/3(x+2)(x-4)=(6-3x)/3(x-4)(x+2)+(x²-16)/3(x+2)(x-4)=(6-3x+x

原式=(x^2-8x+16)^3(x+1)^6/(x^2-2x+1)^3(x-4)^4(x+2)^2=(x-4)^6(x+1)^6/(x-1)^6(x-4)^4(x+2)^2=(x-4)^2(x+1)

原式=x(x+4)/(x-2)(x+4)-(x+2)/(x+2)(x-2)=x/(x-2)-1/(x-2)=(x-1)/(x-2)再问：计算a+b分之b²-【b】再答：采纳我，重新问

因为x又x分之1=3,即x+1/x=3所以x+1/x=7则x^4+1/x^4=47所以：(x^10+x^8+x^2+1)/(x^10+x^6+x^4+1)=

x+2分之1+x^2-4分之x+6-x^-4x+4分之2x+1=x-2/x^2-4+x+6/x^2-4-(2x+1/x^-4x+4)=2x+4/x^2-4--(2x+1/x^-4x+4)=2/x--2

3/4x-11/20x4=2两边乘2015x-44=4015x=44+4015x=84x=5.6