5/9x÷1/3=25/18

解方程 ①11x+25=18x+9-5x ②x+3=4+1/2x 0.75x-1/2x=-5;3x+5=4x+1;3X+5=4X+18;1-7x=x-7;9x+8-7x=3x;-(x-2 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 x+3/x+1-x+5/x+3-x+7/x+5+x+9/x+7=0 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 (x-2)(x2-6x-9)-x(x-5)(x-3)其中x= -1/3 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 先化简,再求值(1)1/x-3÷x-4/x²-6x+9+1-x/x+4,其中x=5 1/x(x+3)+1/(x+3)(x+6)+1/(x+6)(x+9)=3/2x+18