First take the log on both sides,
lny = ln[(x3+2)2(x5+4)4]
Using logarithm properties, we can simplify.
lny = 2ln(x3+2) + 4ln(x5+4)
Differentiate on both sides.
(1/y)(dy/dx) = (2/x3+2)*(3x2) + (4/x5+4)(5x4)
Multiply by y on both sides
dy/dx = y[(2/x3+2)*(3x2) + (4/x5+4)(5x4)]
Now, you the substitute the value of y
dy/dx = [(x3+2)2(x5+4)4]*[(2/x3+2)*(3x2) + (4/x5+4)(5x4)]
I hope this helps. If you have any question, please let me know in the comments.