||'''Book'''|| Advanced Engineering Mathematics ||
 ||'''Author'''|| Erwin Kreyszig ||
 ||'''Edition'''|| 8th Edition ||

/* code_begins */

{{{
theta=var('theta')   #define a variable theta
r=function('r',theta)   #define r to be a function of that variable
t= diff(r,theta)-r
desolve(t,[r,theta])}}}

/* code_ends */

 * '''Solution by''': 
   * <Rachit Jha>, <student>, <IIT ROORKEE>
   * <Arnab Basu>, <Student>, <IIT ROORKEE>
   * <Saurabh Agarwal>, <student>, <IIT ROORKEE>