If f(x) = 4^(x+1) , what is f(2x+3) in terms of f(x) ?

Jul 11, 2016

$16 \cdot {\left[f \left(x\right)\right]}^{2}$

Explanation:

$f \left(x\right) = {4}^{x + 1}$

$f \left(2 x + 3\right) = {4}^{\left(2 x + 3\right) + 1}$

$f \left(2 x + 3\right) = {4}^{x + 1} \cdot {4}^{x + 1} \cdot {4}^{2}$
$f \left(2 x + 3\right) = f \left(x\right) \cdot f \left(x\right) \cdot {4}^{2}$
$f \left(2 x + 3\right) = 16 \cdot {\left[f \left(x\right)\right]}^{2}$