Найти производную , спасибо )

1) $f'=5$
2) $f'=3x^{2}+4x-5$
3) $f= \frac{3+2x}{x-5}$
$f'=( \frac{3+2x}{x-5})'= \frac{2(x-5)-3-2x}{(x-5)^{2}}=\frac{2x-10-3-2x}{(x-5)^{2}}=-\frac{13}{(x-5)^{2}}$
4) $f=e^{x}*2^{x}$
$f'=e^{x}*2^{x}+e^{2}*2^{x}*ln2=e^{x}*2^{x}(1+ln2)$
5) $f= \frac{x^{2}-5}{x+1}$
$f'= \frac{2x(x+1)-x^{2}+5}{(x+1)^{2}}= \frac{2x^{2}+2x-x^{2}+5}{(x+1)^{2}}=\frac{x^{2}+2x+5}{(x+1)^{2}}=\frac{(x^{2}+2x+1)+4}{(x+1)^{2}}=\frac{(x+1)^{2}+4}{(x+1)^{2}}=1+\frac{4}{(x+1)^{2}}$
6) $f=x^{ \frac{1}{8}}$
$f'=\frac{1}{8}x^{ \frac{1}{8}-1}=\frac{1}{8}x^{- \frac{7}{8}}=\frac{1}{8 \sqrt[8]{x^{7}}}$
7) $f=5x^{-6}$
$f'=-30x^{-6}=- \frac{30}{x^{6}}$
8) $f'=108-3x^{2}$
$108-3x^{2} \leq 0$
$-3x^{2} \leq -108$
$3x^{2} \geq 108$
$x^{2} \geq 36$
$x \leq -6$ U $x \geq 6$