f(x)=c
f(x)=x^n
f(x)=sin(ax)
f(x)=Cos(ax)
f(x)=e^ax
f(x)=ln(ax)
f(x)=tan(x)
f(x)=cot(x)
f(x)=cosec(x)
f(x)=arcsin(x)
f(x)=arcos(x)
f(x)=arctan(x)
