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If A, B and C are square matrices of same order, then AB = AC always implies that B = C - Mathematics

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Question

If A, B and C are square matrices of same order, then AB = AC always implies that B = C

Options

  • True

  • False

MCQ
True or False

Solution

This statement is False.

Explanation:

Let A = `[(1, 0),(0, 0)]`

B = `[(0, 0),(2, 0)]`

And C = `[(0, 0),(3, 4)]`

∴ AB = `[(1, 0),(0, 0)] [(0, 0),(2, 0)] = [(0, 0),(0, 0)]`

AC = `[(1, 0),(0, 0)] [(0, 0),(3, 4)] = [(0, 0),(0, 0)]`

Here AB = AC = 0 but B ≠ C.

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Chapter 3: Matrices - Exercise [Page 64]

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NCERT Exemplar Mathematics [English] Class 12
Chapter 3 Matrices
Exercise | Q 97 | Page 64

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