# Ex 1.3, 1 - Chapter 1 Class 12 Relation and Functions

Last updated at Sept. 24, 2018 by Teachoo

Last updated at Sept. 24, 2018 by Teachoo

Transcript

Ex 1.3, 1 - Chapter 1 Class 12 Relation and Functions - NCERT Let f: {1, 3, 4} → {1, 2, 5} and g: {1, 2, 5} → {1, 3} be given by f = {(1, 2), (3, 5), (4, 1)} and g = {(1, 3), (2, 3), (5, 1)}. Write down gof. Let us draw figures to denote set f and set g We see that gof (1) = 3 gof (3) = 1 gof (4) = 3 So, gof = { (1, 3), (3, 1), (4, 3)}

Chapter 1 Class 12 Relation and Functions

Concept wise

- Relations - Definition
- Empty and Universal Relation
- To prove relation reflexive, transitive, symmetric and equivalent
- Finding number of relations
- Function - Definition
- To prove one-one & onto (injective, surjective, bijective)
- Composite functions
- Composite functions and one-one onto
- Finding Inverse
- Inverse of function: Proof questions
- Binary Operations - Definition
- Whether binary commutative/associative or not
- Binary operations: Identity element
- Binary operations: Inverse

About the Author

Davneet Singh

Davneet Singh is a graduate from Indian Institute of Technology, Kanpur. He has been teaching from the past 9 years. He provides courses for Maths and Science at Teachoo.