# The graphs of F, F', and F"

• Nov 14th 2012, 08:08 PM
theunforgiven
The graphs of F, F', and F"
Hey guys. :) I have the following assignment that I should turn in by Friday.
I would appreciate if someone could double check my answers for me and point out my mistakes if there are any.

http://img405.imageshack.us/img405/76/scan0002xl.jpg

EDIT: Here is a copy of the original paper.
• Nov 14th 2012, 08:15 PM
MarkFL
Re: The graphs of F, F', and F"
I would say all but the first is correct.
• Nov 14th 2012, 08:16 PM
theunforgiven
Re: The graphs of F, F', and F"
Quote:

Originally Posted by MarkFL2
I would say all but the first is correct.

What's the wrong with the first one? Care to explain? :)
• Nov 14th 2012, 08:26 PM
MarkFL
Re: The graphs of F, F', and F"
It F is as you say, then from the curve you have labelled F'', F should be concave down since F'' < 0.

It appears one curve is a cubic, the other a quadratic and the third is linear...
• Nov 14th 2012, 08:34 PM
theunforgiven
Re: The graphs of F, F', and F"
• Nov 14th 2012, 08:39 PM
MarkFL
Re: The graphs of F, F', and F"
Yes, that is correct.

Notice that the curve you have labelled F' decreases down to (nearly) zero then increases again, which matches the slope of F. Notice also that the line you have labelled F'' begins negative and increases to become positive, which matches the slope of F'.
• Nov 14th 2012, 08:41 PM
theunforgiven
Re: The graphs of F, F', and F"
Quote:

Originally Posted by MarkFL2
Yes, that is correct.

Notice that the curve you have labelled F' decreases down to (nearly) zero then increases again, which matches the slope of F. Notice also that the line you have labelled F'' begins negative and increases to become positive, which matches the slope of F'.

I get it. Thank you so much! :)