You don't really need logs to solve this, just a little logic. Since the right side is a power of 2, we can write the left side to be a power of 2 as well. Let's put everything under the square root:
√(2⁵ * 2⁵ * 2) = 2^a
√(2¹¹) = 2^a
2^(11/2) = 2^a
Now that we have two values that are equal, and both bases are the same, the exponents must be the same: