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Question
If A = [aij] is a 2 × 2 matrix such that aij = i + 2j, write A.
Solution
Here
`a_ij = i + 2j, 1≤ i≤2 and 1≤ j≤2`
\[ \therefore a_{11} = 1 + 2\left( 1 \right) = 3, a_{12} = 1 + 2\left( 2 \right) = 1 + 4 = 5\]
`⇒ a_21 = 2 + 2( 1)==4 and a_22 = 2 + 2( 2 ) = 2 + 4 = 6`
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