I assume you are being asked to take the derivative dy/dx. If not, then what is the question?
For this, you will use the chain rule: If u is a function of x, then the derivative of f(u) is:
d/dx(f(u)) = df/du * du/dx
Simple example: y = sin (3x3)
y' = cos(3x3) * 9x2
In your problem, u = x3 + log2 x
then dy/dx = 3*sin2 (x3 + log2 x) * u'