220+230+240+250=( )x( )
240=()X()X()X()
240-x=(260-x)*80%
6x-2(340-3x)=220 18+0.4x=22.2-x
若1+x+x*x+x*x*x=0,求x+x*x+x*x*x+.+x(2000次幂)
(x/x-1)+(5x-2)/x*x-x=1 求x(有图)
f(x)=x²+3x|x-2|
(x/5+60)+(x/4-60)+220=x 4x+5x+4400=20x 请问是怎么推导出来的
f(x)=-x^2+2x(x>0) 0(x=0) x^2-2x(x
解方程(x-2)X(x的平方-6x-9)=x(x-5)X(x-3)
(1) x-3/x-2 - x-5/x-4=x-7/x-6 - x-9/x-8
解方程:(x-8)/(x-3)-(x-9)/(x-4)=(x+7)/(x+8)-(x+2)/(x+3)
3/x-1=4/x 6/x+1=x+5/x(x+1)