Evaluating elasticity
posted by Miranda on .
The demand function for a certain item is x = 35(sqrt(32p^2))
Evaluate the elasticity at 5. E(5)=
I don't know how to find elasticity, so i don't know how to start this problem. If someone could explain elasticity i think that i could figure it out.

Isn'n
Elasticity =  ddemand/dprice * P/q ?
so here
elasticity=  dx/dp * p/x
I assume you can take the derivative, put p=5 (and x(5)) and compute E. 
dx/dp = 35*(1/2)*(2p)/sqrt(32p^2)
= 35/sqrt(32p^2)
Now evaluate E(x) = (p/x)* (dx/dp)
@ p=5
x(5) = 35 sqrt 5
and put it all together.
A few numbers will cancel, simplifying the result.