Mechanics of Fluids Tweet

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1. Mechanics of Fluids
Hi there,

I have got a question to you all:

Differentiate this equation to determine the value of z2/z1 for which it is a maximum.

I see a few ways to approach it, but I have no answer to compare. Can anyone help me, please?
2. Re: Mechanics of Fluids
Any help? I just want to know, how would you do it. Q,b,g treat as constants. Multiply both sides by z12? Then you differentiate constants, so you get 0. Then you differentiate the other side and you get something?
3. Re: Mechanics of Fluids
(Original post by Norbas)
Any help? I just want to know, how would you do it. Q,b,g treat as constants. Multiply both sides by z12? Then you differentiate constants, so you get 0. Then you differentiate the other side and you get something?
??
4. Re: Mechanics of Fluids
Why z2/z1 = 2/3? How did you get this?
Last edited by Norbas; 21-05-2012 at 23:44.
5. Re: Mechanics of Fluids
you take z2/z1 as being your variable, call it x, the lhs of the equation is a constant, call it k:
so k=2x²-2x^3
Differentiate it and you'll get an answer.