Does l'hospitals rule work here?:
[tex]\lim_{h\to_0}\frac{f\left(8+h\right)f\left(8\right)}{h}[/tex] for [tex]f\left(x\right)=x^\frac{4}{3}[/tex]
then i would get,
[tex]\lim_{h\to_0}\frac{f\left(8+h\right)}{1}[/tex]
then,
[tex]=\frac{\left(8\right)^\frac{4}{3}}{1}[/tex] ?
is that it?...
