The problem is: Find the absolute maximum and absolute minimum values offon the given interval.

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- Nov 3rd 2007, 02:16 PM #1

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- Nov 3rd 2007, 02:21 PM #2
first check the endpoints. that is, find f(-1) and f(5).

then search for the critical values. that is, find f'(t) and set it equal to zero and solve for t. then find all f(c) where c represents a critical value, that is, one of the t's you solved for just before. which ever one of these values is the greatest (you include the endpoints as well) is the absolute max, whichever is the lowest is the absolute min

can you continue?

- Nov 3rd 2007, 02:53 PM #3

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- Nov 3rd 2007, 03:03 PM #4

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Ok actually, I have one more question. I'm not getting the min correct for some reason but I got the max. So, I found the critical point of +or- sqr root of 12.5. So I got the max of 12.5 from f(sqr root of 12.5). Then using the neg of the critical number, I got -12.5, but it's not the right answer...which I don't understand why.

- Nov 3rd 2007, 03:48 PM #5

- Nov 4th 2007, 04:33 AM #6

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I did do that. f(-1)=-4.89, f(0)=0

Then I plug in f(-squ root of 12.5), when you do that, t is squared inside the square root. So (-squ root of 12.5)^2 would just give me 12.5. Then 25-12.5=12.5 square root it, times -square root of 12.5 would just get rid of the square root to give me -12.5. That's what I got. What did I do wrong?