8/9x=1/6*16/51

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), x/(x-2)+(x-9)/(x-7)=(x+1)/(x-1)+(x-8)/(x-6)谁会解这道方程题 分式方程.x/(x-2)+(x-9)/(x-7)=(x+1)/(x-1)+(x-8)/(x-6) x/(x-2)+(x+9)/(x-7)=(x+1)/(x-1)+(x-8)/(x-6)怎样解这道方程 解方程：x/(x-2)+(x-9)/(x-7)=(x+1)/(x-1)+(x-8)/(x-6) （1） x-3/x-2 - x-5/x-4=x-7/x-6 - x-9/x-8 1x+2x+3x+4x+5x+6x+7x+8x+9x+10x+11x+12x+13x+14x+15x=550 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 |X-1|+|X-2|+|X-3|+|X-4|+|X-5|+|X-6|+|X-7|+|X-8|+|X-9|+|X-10| x+2x+3x+4x+5x+6x+7x+8x+9x=9x-8x-7x-6x-5x-4x-3x-2x-x.x等于多少?