7*1+10*2+x*3+8*4+(11-x)*5=40*2.5
1x+2x+3x+4x+5x+6x+7x+8x+9x+10x+11x+12x+13x+14x+15x=550
|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),
(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()加9x()+10x()=1980
1X?+2X?+3X?+4X?+5X?+6X?+7X?+8X?+9X?+10X?=1980求?是多少
1+2x+3x^2+4x^3+5x^4+6x^5+7x^6+8x^7+9x^8+10x^9+11x^10当x=-1时的值
2x平方+3x=3 (用配方) x(2x-5)=4x-10 x平方+5x+7=3x+11 1-8x+16x平方=2-8x
已知1+x+x^2+x^3=0,求x+x^2+x^3+x^4+x^5+x^6+x^7+x^8的值
(X+2)/(X+1)-(X+4)/(X+3)=(X+6)/(X+5)-(X+8)/(X+7)
解方程 x+2/x+1+x+8/x+7=x+6/x+5+x+4/x+3