Multiplication of a Matrix by a Number (Sample Questions)


Example 1:
Express the following as single matrix.

(a) 3 ( 1 4 3 2 ) + 2 ( 3 1 3 4 )

(b) 2 ( 1 0 9 4 ) 4 ( 2 2 3 6 ) 1 3 ( 9 3 6 15 )

Solution:
(a) 3 ( 1 4 3 2 ) + 2 ( 3 1 3 4 ) = ( 3 × 1 3 × ( 4 ) 3 × ( 3 ) 3 × 2 ) + ( 2 × ( 3 ) 2 × 1 2 × 3 2 × ( 4 ) ) = ( 3 12 9 6 ) + ( 6 2 6 8 ) = ( 3 + ( 6 ) 12 + 2 9 + 6 6 ( 8 ) ) = ( 3 10 3 14 )


(b) 2( 1 0 9 4 )4( 2 2 3 6 ) 1 3 ( 9 3 6 15 ) =( 2 0 18 8 )( 8 8 12 24 )( 1 3 ×(9) 1 3 ×(3) 1 3 ×(6) 1 3 ×15 ) =( 2 0 18 8 )( 8 8 12 24 )( 3 1 2 5 ) =( 2(8)(3) 08(1) 1812(2) 8(24)5 ) =( 9 7 8 11 )


2 Comments to “Multiplication of a Matrix by a Number (Sample Questions)”

  1. Hello, the answer for b is (9,-7,8,11) because of 18 – 12 -(-2) is 8

    1. Dear Nadin Husin,
      thanks for pointing out our mistake, correction had been made accordingly.

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