5x-2=7x+8 3=3/2x+16 1-3/2x=3x+2/5
x+2x+3x+4x+5x+6x+7x+8x+9x=9x-8x-7x-6x-5x-4x-3x-2x-x.x等于多少?
x^5+x^4 = (x^3-x)(x^2+x+1)+x^2+x
已知1+x+x^2+x^3=0,求x+x^2+x^3+x^4+x^5+x^6+x^7+x^8的值
y=(x-1)(x-2)(x-3)(x-4)(x-5)(x-6)(x-7)(x-8)(x-9)(x-10)的导数在x=1
设函数f(x)=(x-1)(x-2)(x-3)(x-4)(x-5)(x-6)(x-7)(x-8)(x-9)(x-10),
(3-x)/(1-x)-(5-x)/(7-x)+(x^2-x)/(x^2-8x+7)=1
(1) x-3/x-2 - x-5/x-4=x-7/x-6 - x-9/x-8
(X+2)/(X+1)-(X+4)/(X+3)=(X+6)/(X+5)-(X+8)/(X+7)
解方程 x+2/x+1+x+8/x+7=x+6/x+5+x+4/x+3
1x+2x+3x+4x+5x+6x+7x+8x+9x+10x+11x+12x+13x+14x+15x=550
解方程x/(x-2)=2x/(x-3)+(1-x)/(x-5x+6)
2x+3x+4x+5x+x+6x+7x=100