From: <HIDDEN>
Newsgroups: comp.soft-sys.matlab
Subject: Re: How to solve transecedental equation using matlab
Date: Sat, 14 Feb 2009 21:33:02 +0000 (UTC)
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Perhaps I missed something.  
We know tanh(a*x) has only one root, x = 0. But tan(a*x) has many roots because it is periodic, plotting tanh(a*x) and -tan(a*x) on the same graph, we can see multiple intersection points.

ezplot('-tan(2*x)',[-4*pi 4*pi])
hold on
ezplot('tanh(2*x)',[-4*pi 4*pi])