2x+3x=10 2.1x+1.4=35 7x减1.4x=1.28 明天早上就交,

2x+3x=10 2.1x+1.4=35 7x减1.4x=1.28 上面是五年级解方程,谢谢,明天早上就交,急! .明天要交.1.(x-2)/(x+3)=3-(2x^2-13)/(x^2-9)2[A/(X-5)+{B/(X+2)}]= x除以5=1.4 解方程,快,我明天就交了! 用递归法求y=x-(x*x*x/3!)+(x*x*x*x*x/5!)-(x*x*x*x*x*x*x/7!)+. x+2x+3x+4x+5x+6x+7x+8x+9x=9x-8x-7x-6x-5x-4x-3x-2x-x.x等于多少? 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+12)(x-2)+(x+7)(x+8)-(x+5)(x-10),其中x=2 2x+3x+4x+5x+x+6x+7x=100 1x+2x+3x+4x+5x+6x+7x+8x+9x+10x+11x+12x+13x+14x+15x=550 [3x/2-x+y/2(3x/x+y-x-y)]÷x/x-y,其中5x+3y=0.化简并求值.明天交的! 1x()+2x()+3x()+4x()+5x()+6x()+7x()+8x()加9x()+10x()=1980