Could some one please help me... I'm terrible at math and I need solve this for economics.

What is the maximum of the function.

its a growth formula.... and s is stock and k is a constant.

g(s) = s (1 - s/k)

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- December 3rd 2010, 11:41 AMthainyFinding Maximum
Could some one please help me... I'm terrible at math and I need solve this for economics.

What is the maximum of the function.

its a growth formula.... and s is stock and k is a constant.

g(s) = s (1 - s/k) - December 3rd 2010, 12:02 PMAckbeet
Is that

or

Technically, you wrote the first.

What ideas have you had so far? - December 3rd 2010, 12:08 PMthainy
\displaystyle g(s)=s\left(1-\frac{s}{k}\right),

Hmmm well..... I've never taken calculus... so I don't know why our prof is even asking this question... but my first though was to take the derivative but I've never done one with two varriables before. - December 3rd 2010, 12:10 PMAckbeet
I doubt that you're asked to treat k as a variable. When I see this sort of maximization problem, I think of maximizing g as a function of s (note that you have g(s), not g(s,k)). Since you have a parabola, there are two methods of solving this problem. You could do the calculus method of taking the derivative and setting it equal to zero. Or, if you feel uncomfortable with that, then just complete the square. Pick a method, and see what happens.

- December 3rd 2010, 12:27 PMthainy
Yes I've said before.... the last time I took math was in grade 12... so... I'm not exactly sure how to do either of those things.... woud you mind giving me a hint?

- December 3rd 2010, 12:32 PMAckbeet
All right, let's complete the square, then.

The idea with completing the square is this. However, in your case, you're going to end up with something that looks like this:

Your goal is to find so that this holds. Make sense? - December 3rd 2010, 12:35 PMthainy
Yes so much! thankyou!

- December 3rd 2010, 12:37 PMAckbeet
Good. Now once you have the expression looking like post # 6, how would you find the maximum?