2.1.71 Calculation of Limits

Condition: calculate the limits: 1) \ (\ lim _ {x \ rightarrow 4} \ frac {4^{x} -x^{4}} {(x-4)^{2}} \) 2) \ (\ lim {x \ rightarrow 0} \ frac {\ arctan 4 x- \ tan 4 x} {x^{3}} \), 3) \ (\ lim _ {x \ rightarrow+\ infty} \ frac {x^{4}+4^{4 x^{3} -2} -2} -2} -2} -2} -2} -2} -2} -2} -2} -2} -2} -2} -2} -2} -2} \).