I need to find the maximum of this equation by finding the derivative and setting it to zero:

Now, solving for the derivative using the chain rule for the first operand, and using product rule+chain rule for the second operand, I get the following:

get common denominators:

Assuming that is correct so far, where do I go from there? Do I multiply through to cancel the denominator to get the following:

If that's correct, then what do I do?