$20$

Multiple Choice $4$ points

Let $f(x)=\frac{4}{x}ln(ax),$ where $a$ is a positive constant. Find $f^{\text{'}}(x).$

$f^{\text{'}}(x)=\frac{4}{x^2}-\frac{a}{x}$

$f^{\text{'}}(x)=-\frac{4}{x^2}-\frac{1}{x}$

$f^{\text{'}}(x)=\frac{1}{x}\frac{1}{a}$

$f^{\text{'}}(x)=-\frac{4}{x^2}\frac{1}{x}$

None of the other answers listed are correct

$f^{\text{'}}(x)=-\frac{4}{x^2}\frac{a}{x}$

$f^{\text{'}}(x)=\frac{4}{x^2}\frac{a}{x}$