Exercise 3.4, Question 1
A and B are inverses of each other only if: (A) \(AB = BA\) (B) \(AB = BA = O\) (C) \(AB = O, BA = I\) (D) \(AB = BA = I\)
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- By definition, both products must be the identity.
Answer: (D)
NCERT Solutions for Class 12 Maths Chapter 3 Exercise 3.4
Exercise 3.4: Invertible matrices. B is the inverse of a square matrix A when \(AB = BA = I\); the inverse, if it exists, is unique, and \((AB)^{-1} = B^{-1}A^{-1}\).
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Exercise 3.4 questions and solutions
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