2/5X+(1-2/5)*5/9-10+74=X

|X-1|+|X-2|+|X-3|+|X-4|+|X-5|+|X-6|+|X-7|+|X-8|+|X-9|+|X-10| 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), 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 已知x=9/2 求:[(x^+7x+10)/(x^2+6x+5)]×[(x^3+1)/(x^2 x^5+x^4 = (x^3-x)(x^2+x+1)+x^2+x （1） x-3/x-2 - x-5/x-4=x-7/x-6 - x-9/x-8 (4x+2)/x+(4x-22)/(x-5)=(x-6)/(x-4)+(7x+9)/(x+1) (x-2)(x2-6x-9)-x(x-5)(x-3)其中x= -1/3 x+2x+3x+4x+5x+6x+7x+8x+9x=9x-8x-7x-6x-5x-4x-3x-2x-x.x等于多少?