Why does this equation have no solution?

[warwick]

(pi/8) sec^2(pix/8) = (4/x^2) (derivative)

On the interval [1,2]

I was to find the critical numbers and thus determine the absolute extrema.

Damn. I'm tired. :roll:

 

[stapel]

Your subject line refers to trying to find a solution to the equation. But then your post refers to finding absolute max/min values on an interval. Which are you needing to do?

When you reply, please include the work you have done so far, even if you think it is wrong. Thank you.

Eliz.

 

[warwick]

Your subject line refers to trying to find a solution to the equation. But then your post refers to finding absolute max/min values on an interval. Which are you needing to do?

When you reply, please include the work you have done so far, even if you think it is wrong. Thank you.

Eliz.

Sorry. I forgot to mention the equation is a derivative.

 

[stapel]

I forgot to mention the equation is a derivative.

Was it the equation you were given, or did you differentiate something to get to this equation?

Thank you.

Eliz.

 

[warwick]

I forgot to mention the equation is a derivative.

Was it the equation you were given, or did you differentiate something to get to this equation?

Thank you.

Eliz.

Well, since I said the equation I gave is a derivative, that would mean I had to differentiate something else to get it.

Yes, that is the derivative which would allow me to find the critical values.

 

[galactus]

In other words, you have to solve this equation for x.

Try Newton's method. It may work as well as any for this. Try an initial guess of 2.

I get x=2.1344839886

 

[stapel]

I had to differentiate something else to get it.

It might help if you posted the original exercise (including the original equation), as the difficultly may have sprung from some earlier step in the process.

Thank you.

Eliz.