Question

Why is this math answer wrong? Please help regarding natural logs?

Answer 1

$\bf 7275(2^k)^3~~+~~5723\cdot 2^k~~+~~4725k(2^k)^3~~+~~3717k2^k~\hfill \begin{cases} n=2^k\\ k=\frac{ln(n)}{ln(2)}\\[-0.5em] \hrulefill\\ n=2^{\frac{ln(n)}{ln(2)}} \end{cases} \\\\[-0.35em] ~\dotfill$

$\bf 7275n^3~~+~~5223n~~+~~4725\cdot \cfrac{ln(n)}{ln(2)}(n^3)~~+~~3717\cfrac{ln(n)}{ln(2)}(n) \\\\\\ 7275\left( 2^{\frac{ln(n)}{ln(2)}} \right)^3+5273\left( 2^{\frac{ln(n)}{ln(2)}} \right)+4275\cfrac{ln(n)}{ln(2)}\left( 2^{\frac{ln(n)}{ln(2)}} \right)^3+3717\cfrac{ln(n)}{ln(2)}\left( 2^{\frac{ln(n)}{ln(2)}} \right)$