Mathbee CBSE Mathbee · CBSE Class 12 Maths
Class 12 Relations And Functions · Long Answer3 Markstypes_of_relations

Class 12 Maths · Relations And Functions · Long Answer #214

On N×N define (a,b)R(c,d) iff a²+d²=b²+c². Prove equivalence.

✅ Step-by-Step Solution

Final Answer: An equivalence relation.
  1. Rewrite the condition as a²−b²=c²−d². Each pair has the same squared difference as itself, proving reflexivity.
  2. Equality of the squared differences is symmetric, so (a,b)R(c,d) implies (c,d)R(a,b).
  3. If a²−b²=c²−d² and c²−d²=e²−f², then a²−b²=e²−f², proving transitivity.
  4. All three properties hold; R is an equivalence relation.

📋 CBSE Stepwise Marking Scheme

  • [0.5 marks] Rewrite the condition as a²−b²=c²−d². Each pair has the same squared difference as itself, proving reflexivity.
  • [1 mark] Equality of the squared differences is symmetric, so (a,b)R(c,d) implies (c,d)R(a,b).
  • [1 mark] If a²−b²=c²−d² and c²−d²=e²−f², then a²−b²=e²−f², proving transitivity.
  • [0.5 marks] All three properties hold; R is an equivalence relation.

Master Chapter 1: Relations And Functions

Practise interactive questions, flashcards, visual mind maps, and timed board tests for Relations And Functions.
📘 Chapter Notes & All Exercises 🚀 Open Interactive Workspace →
← Previous Question
Find the domain and range of R={(a,a³):a is a prime less than 5}.
Next Question →
On R, let aRb iff a≤b³. Test reflexivity, symmetry and transitivity.

More Practice Questions in Relations And Functions

Related Questions in Relations And Functions