The given reaction scheme is:

E + S ES1 ES2 E + P

The reactions indicated by each arrow are all elementary reactions, and the indicated k is the reaction rate for each reaction.

is a constant ES1 and ES2 are different types of reaction intermediates. Both equilibrium reactions are

Note fast assuming that the reaction that reaches equilibrium quickly and produces the final P is relatively slow

Use the equilibrium approximation to derive the reaction rate equation for the above reaction.