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If possible, using elementary row transformations, find the inverse of the following matrices [23-3-12211-1] - Mathematics

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Question

If possible, using elementary row transformations, find the inverse of the following matrices

`[(2, 3, -3),(-1, 2, 2),(1, 1, -1)]`

Sum

Solution

Here, A = `[(2, 3, -3),(-1, 2, 2),(1, 1, -1)]`

Put A = IA

`[(2, 3, -3),(-1, 2, 2),(1, 1, -1)] = [(1, 0, 0),(0, 1, 0),(0, 0, 1)]"A"`

R1 → R1 – 2R3 and R2 → R2 + R1

`[(0, 1, -1),(0, -1, 1),(1, 1, -1)] = [(1, 0, -2),(0, 1, 1),(0, 0, 1)]"A"`

R1 → R1 + R

`[(0, 0, 0),(0, -1, 1),(1, 1, -1)] = [(1, 1, -1),(0, 1, 1),(0, 0, 1)]"A"`

First row on L.H.S. contains all zeros

So the inverse of the given matrix A does not exist.

Hence, matrix A has no inverse.

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Chapter 3: Matrices - Exercise [Page 59]

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NCERT Exemplar Mathematics [English] Class 12
Chapter 3 Matrices
Exercise | Q 51.(ii) | Page 59

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