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Examine the consistency of the system of equations. x + y + z = 1 2x + 3y + 2z = 2 ax + ay + 2az = 4 - Mathematics

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Question

Examine the consistency of the system of equations.

x + y + z = 1

2x + 3y + 2z = 2

ax + ay + 2az = 4

Sum

Solution

Let, `A = [(1,1,1),(2,3,2),(a,a,2a)], X = [(x),(y),(z)], B = [(1),(2),(4)]`

`abs A = [(1,1,1),(2,3,2),(a,a,2a)]`

`= 1 xx (3 xx 2a - a xx 2) - 1 xx (2 xx 2a - a xx 2) + 1 xx (2 xx a - a xx 3)`

= 4a - 2a - a

`= a ne 0`

a ≠ 0 and the system of equations is consistent.

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Chapter 4: Determinants - Exercise 4.6 [Page 136]

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NCERT Mathematics [English] Class 12
Chapter 4 Determinants
Exercise 4.6 | Q 4 | Page 136

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