Thread: Simplify Expression for Hydraulics

Hi guys, i am currently preparing for one of my exams in hydraulics
.and here is the expression that I am failing to solve.

h/2 + L*h^3 / 12 * h * L * h/2

So my goal is to try to find a shorter expression for this.
and I get 2h/3

But our teachers solution is insisting on that it should be
h * 3/2

how did he get to that?

It would be useful if you would use brackets, because the expression is not clear to me.
?

...
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