f(x) = 2x + |x|
f(2x)=2(2x)+|2x| =4x+|2x|
f(-x) = -2x + |-x| = -2x + |x|
f(2x) + f(-x) - f(x) = 4x+|2x| -2x + |x| - 2x - |x|
= |2x|
![[Post New]](/templates/default/images/icon_minipost_new.gif){kind=icon}
![[Up]](/templates/default/images/icon_up.gif "[Up]"){kind=icon}
802
