18/25*x=2/9 7/8x*5/7=7/15
x+2x+3x+4x+5x+6x+7x+8x+9x=9x-8x-7x-6x-5x-4x-3x-2x-x.x等于多少?
1x+2x+3x+4x+5x+6x+7x+8x+9x+10x+11x+12x+13x+14x+15x=550
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),
解方程:(x+3)/(x+2)-(x+5)/(x+4)=(x+7)/(x+6)-(x+9)/(x+8)
(1) x-3/x-2 - x-5/x-4=x-7/x-6 - x-9/x-8
(x+12)(x-2)+(x+7)(x+8)-(x+5)(x-10),其中x=2
x-4/x-5 - x-5/x-6=x-7/x-8 - x-8/x-9求x=?
0.75x-1/2x=-5;3x+5=4x+1;3X+5=4X+18;1-7x=x-7;9x+8-7x=3x;-(x-2
a*b=2×a+b 计算x*2x*3x*4x*5x*6x*7x*8x*9x=3039 x=
1x()+2x()+3x()+4x()+5x()+6x()+7x()+8x()加9x()+10x()=1980
1X?+2X?+3X?+4X?+5X?+6X?+7X?+8X?+9X?+10X?=1980求?是多少