View source for Errata: In Exercise 4.6, Pm/J should be taken as 1 and factor of 1/2 is misplaced

{{errata page
| chapter = Dynamic Behavior
| page = 128
| line = 3
| contributor = R. M. Murray
| date = 8 Jul 08
| version = First printing
| text = 
Part (c) of the exercise should read:
<blockquote>
Show that <font color="blue">if <math>P_m / J =1</math></font> there is a solution through the saddle
that satisfies 
<center><amsmath>
  \frac{1}{2} \Bigl(\frac{d\varphi}{dt} \Bigr)^2 - \varphi + \varphi_0
  - a\cos{\varphi} - \sqrt{a^2-1}=0.
</amsmath></center>
</blockquote>
}}