For all CAT 2008 aspirants starting their preparations, an introduction to absolute value (modulus) will help them to strengthen their basics. The credit for this chapter goes to my CAT 2007 students. Teaching in a classroom is a learning experience. A teacher learns more about the topic from students than what he learns from the books. This chapter is dedicated to all my CAT 2007 students who gradually, through their inquisitiveness, forced me to find more about the subject than what I already knew.
To understand absolute value function, we study the function from two different points.