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

/* code_begins */

{{{
t=var('t')
Y=function('Y',t)
DE = diff(diff(Y,t),t) + 2*diff(Y,t) + 2*Y - cos(t) 
de(t)=desolve (DE,[Y,t])
print de(t)
de1(t)=diff(de(t),t)
k1,k2=var('k1,k2')
solve([de(0)==1.2,    
       de1(0)==1.4],k1,k2)
de(t)=de(t).subs(k1 =2, k2= 1)
print 'The motion of the given mass-system is' 
print(de(t))
plot(de(t),[0,50])

}}}

/* code_ends */

 * '''Solution by''': 
   * Hardik Gajera,  student,  IISER Pune
   * Lokesh Pimpale,  student,  IISER Pune