I have this function:

$\displaystyle v'=cos(2x)$

and I'm told that

$\displaystyle v=[sin(2x)]/2$

Does that mean if I have a trig function, say

$\displaystyle f= [sin(5x)]/5$

then

$\displaystyle f'=cos(5x)$?

or if

$\displaystyle g=[cos(5x)]/5$

then

$\displaystyle g'=-sin(5x)$?