11(X+1/3)-13X=2
1x+2x+3x+4x+5x+6x+7x+8x+9x+10x+11x+12x+13x+14x+15x=550
(2x-1)/(x-1)(x-2)=(x-5)/(x-2)(x-3) x/2x^2-11x-21=(x+7)/x^2-1
解方程:13x+8=11x -7x+2=2x-4 3x+2=-3+x x-3=-1/2x
已知X=π/3,试求|X+1|-|X+2|+|X+3|-|X+4|.+|X+11|-|X+12|+|X+13|的值
已知x等于负三分之π,|x+1|-|x+2|+|x+3|-|x-4|+...+|x+11|-|x+12|+|x+13|=
x^5+x^4 = (x^3-x)(x^2+x+1)+x^2+x
若x=π/3,|x+1|+|x+3|+...+|x+13|-|x+2|-|x+4|-...-|x+12|
解方程x/(x-2)=2x/(x-3)+(1-x)/(x-5x+6)
x^4+x^3+x^2+x+1=0,x^2006+x^2005+x^2004+x^2003+x^2002
2x-7/4x=13 3x+1/3x=20/21 x-0.28x=12.
解方程3x(2x-3)-(4-2x)x=(1-4x)×(-2x)-11
已知x^-3x=1,求3X^*x-11X^+3x+2的值.