x+10*0.14%x*(1-20%)=2528
x+10*0.14%x*(1-20%)=2528
(X-X*20%-18-(X-X*20%-18)*10%=X*1/2-3(过程)
X+1-3X=5X+10 6-3X=5X-20
解方程(x/x(x+2))+(x/(x+2)(x+4))+.+x/(x+8)(x+10)=1
x-10=4(x-28) 3(x-28)=x+56+28 2(1.5x-30-20)=x 2(2x-20-45)=x-1
x/2+x/8+x/12+x/20=1
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/2+x/6+x/12+x/20+x/30+x/42=1
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