X-0.7X+4=13.
X-0.7X+4=13.
4x+9x=13x
1x+2x+3x+4x+5x+6x+7x+8x+9x+10x+11x+12x+13x+14x+15x=550
若x=π/3,|x+1|+|x+3|+...+|x+13|-|x+2|-|x+4|-...-|x+12|
x^5+x^4 = (x^3-x)(x^2+x+1)+x^2+x
已知 X=4- 根号3 求 (X*X*X*X-6X*X*X-2X*X+18X+23) / (X*X-8X+15)的值
解方程. 0.3x+13=25 4x-6×9=98 7x+3x+26=74 3.8x-x=0.56.
解方程(x+1)(x+3)+4x=-13
13X-4(2X+5)=2(X+11)
3x-7+4x=6x-2.
x+2x+3x+4x+5x+6x+7x+8x+9x=9x-8x-7x-6x-5x-4x-3x-2x-x.x等于多少?
13-2x=4,3x+4×0.5,5(x+4)=55,9÷1.5x=8,1.3x+x=13.8,x-0.7x=6.9,2