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