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


{{{

var ('y,b,c')
y=-cos(x)
b=diff(y,x,2)-y
c=2*cos(x)
bool(b == c)
}}}



 * '''Solution by''': 
   * <YASHWANTH>, <STUDENT>, <SNIST>
   * <SREE LAKSHMI>, <STUDENT>, <SNIST>