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

/* code_begins */

{{{

x = var('x')
y=function('y',x)
DE = diff(y,x,2)-y-2*cos(x)
print "GS:", desolve(DE, [y,x], ics=[0,0,-0.2])
#check for particular solution
yp = -cos(x)
V = diff(yp,x,2)-yp-2*cos(x)
if V == 0:
    print "yp = ", yp, "is a particular solution"
else:
    print "yp = ", yp, "is not a particular solution"

}}}

/* code_ends */

 * '''Solution by''': 
   * Zubin Mehta, Student, IIT Bombay