Re: Help with differential equation

*To*: mathgroup at smc.vnet.net*Subject*: [mg112246] Re: Help with differential equation*From*: Raul Martinez <raulmart at mac.com>*Date*: Mon, 6 Sep 2010 06:36:13 -0400 (EDT)*References*: <201009060814.EAA00386@smc.vnet.net>

You need cos[y[x]]. Raul Martinez On Sep 6, 2010, at 1:14 AM, mathpavi wrote: > Dear experts, > I tried solving the following differential equation using DSolve: > > y' ' [x]+a( y' [x] ) = b( cos[y] ) > > But I got error message which asked me to provide proper arguments for > cos.. > So I changed cos[y] to cos[kx] and obtained solution... > However, I have to solve the equation by keeping cos[y] in order to > obtain a solution of relevance to my work. > Please help. > praveen >

**References**:**Help with differential equation***From:*mathpavi <elvisgraceland@gmail.com>