I was wondering whether the recurrence T(n) = T(n/2) + 2n could be solved by using master theorem, and what would be the way. I tried solving the recurrence but can't. There is no mention to it in CLRS book. Please help. Thanks in advance.

$T(a)=0 \hspace{0.2cm} if \hspace{0.2cm} a=1$ $T(a)=2T(a/2) + ak \hspace{0.2cm} if \hspace{0.2cm} a=2^{p}, p>0$ where $a=\frac{n}{k}$ Answer: $\Theta (n \log (\frac{n}{k}))$, This is while (n/k) is power of 2. How can I solve it using master theorem?