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Find A, if [413] A = [-484-121-363] - Mathematics

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Question

Find A, if `[(4),(1),(3)]` A = `[(-4, 8,4),(-1, 2, 1),(-3, 6, 3)]`

Sum
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Solution

We have, `[(4),(1),(3)]` A = `[(-4, 8,4),(-1, 2, 1),(-3, 6, 3)]`

Let A = `[(x, y, z)]`

∴ `[(4),(1),(3)][(x, y, z)] = [(-4, 8, 4),(-1, 2, 1),(-3, 6, 3)]`

⇒ `[(4x, 4y, 4z),(x, y, z),(3x, 3y, 3z)]  [(-4, 8, 4),(-1, 2, 1),(-3, 6, 3)]`

Comparing elements of both sides

4x = –4

⇒ x = –1

4y = 8

y = 2

and 4z = 4

⇒ z = 1

∴ A = `[(–1, 2, 1)]`

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Chapter 3: Matrices - Exercise [Page 54]

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NCERT Exemplar Mathematics [English] Class 12
Chapter 3 Matrices
Exercise | Q 13 | Page 54

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