Question

ME AJUDEM NESSA PESSOAL POR FAVOR!

Answer 1

a) $f(x)=mx+3$

$x=mf^{-1}(x)+3$

$mf^{-1}(x)=x-3$

$f^{-1}(x)=\dfrac{x-3}{m}$

$f^{-1}(2)=5$

$\dfrac{2-3}{m}=5$

$5m=-1~~\Rightarrow~~m=-\dfrac{1}{5}$.

$f^{-1}(x)=\dfrac{x-3}{-\frac{1}{5}}=\dfrac{x-3}{1}\cdot\dfrac{-5}{1}=-5x+15$.

b) $f(x)=-\dfrac{1}{5}x+3$

$f(2)=-\dfrac{2}{5}+3=\dfrac{15-2}{5}=\dfrac{13}{5}$

c) $f(0)=-\dfrac{1}{5}\cdot0+3=3$

d) $f^{-1}(x)=-5x+15$

$f^{-1}(-2)=-5(-2)+15=10+15=25$

e) $f^{-1}(4)=-5\cdot4+15=-20+15=-5$.