Demand function and finding elasticity

Quote:

Originally Posted by Mathamateur

I wasn't sure whether this should go in the Calculus or Business sections(it's a calculus class but a business themed problem) my apologies if it is in the wrong section.

For the demand function q = 800 - 2p^2 find the elasticity when p = $12 and q is the number of items produced.

Now the definition of elacticity that I have here is:

$E=(\%\mbox{ age change in demand})/(\%\mbox{ age change in price)}=\frac{dq}{dp}\ \frac{p}{q}$ .

Now:

$\frac{dq}{dp}=-4p$ ,

so:

$<br /> E=-4p\ \frac{p}{800-2p^2}<br />$

So if $p=12$ , the:

$<br /> E=-4 \times 12\ \frac{12}{800-288}=-1.125<br />$

RonL