@ashutosh....concavity implies quasiconcavity
and if utility function is quasiconcave then it imples that indifference curves will be convex to the origin....
and it is not neccessary that utility functions r alwys concave.....
if u r able to show that a particular function is quasiconcave den it automatically means that IC will be convex....
Akshay Jain
Masters in Economics
Delhi School of Economics
2013-15