(100+x)*1/3=2/5x 比如x+5=10 x=10-5 x=5

x^5+x^4 = (x^3-x)(x^2+x+1)+x^2+x 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 (x+12)(x-2)+(x+7)(x+8)-(x+5)(x-10),其中x=2 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…+99x=100 解方程：2x+4x+6x...+100x=1-(x+3x+5x+...+99x) 3^x=2^x,求x.5^(x-1)·10^3x=8^x求x