Question

@Michele_Laino

Answer 1

81 right?

Answer 2

I think not, because from the text of your problem, I think you have to calculate the derivative of the function:
\[f(x)=x ^{4}\]
at x=3,
so, being:
\[f'(x)=4x ^{3}\]
we have:
\[f'(3)=4*27=108\]

Answer 3

you can see that, if we perform all calculus, namely:
\[\frac{ (h+3) ^{4}}{ h }=h ^{3}+54h+12h ^{2}+108\rightarrow 108\]
when h--->0