5x-20%x=19.2 3/5:6=(x+3/5):10
x+2x+3x+4x+5x+6x+7x+8x+9x=9x-8x-7x-6x-5x-4x-3x-2x-x.x等于多少?
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
用递归法求y=x-(x*x*x/3!)+(x*x*x*x*x/5!)-(x*x*x*x*x*x*x/7!)+.
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),
解方程(x-2)X(x的平方-6x-9)=x(x-5)X(x-3)
(1) x-3/x-2 - x-5/x-4=x-7/x-6 - x-9/x-8
3/x-1=4/x 6/x+1=x+5/x(x+1)
X+1-3X=5X+10 6-3X=5X-20
2x+3x+4x+5x+x+6x+7x=100
解方程x/(x-2)=2x/(x-3)+(1-x)/(x-5x+6)
1x+2x+3x+4x+5x+6x+7x+8x+9x+10x+11x+12x+13x+14x+15x=550
已知3x*x-x=1,求6x*x*x+7x*x-5x+2000