Let A={pmatrix} 2 & 3 \\ 4 & 5 {pmatrix} ; B{pmatrix} 1 & 5 \\ 6 & 7 {pmatrix} then the value 3A-B

Correct Answer is : (5468){pmatrix} 5 & 4 \\ 6 & 8 {pmatrix}(5648)

{pmatrix} -4 & -14 \\ 9 & 11 {pmatrix}

{pmatrix} -4 & -14 \\ 9 & -11 {pmatrix}

{pmatrix} 4 & -14 \\ 9 & 11 {pmatrix}

{pmatrix} 5 & 4 \\ 6 & 8 {pmatrix}

Correct Answer is : (5468){pmatrix} 5 & 4 \\ 6 & 8 {pmatrix}(5648)

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Matrices

Question : 33 of 36

Marks: +1, -0

Let

A=\begin{pmatrix} 2 & 3 \\ 4 & 5 \end{pmatrix} ; B\begin{pmatrix} 1 & 5 \\ 6 & 7 \end{pmatrix}

3A-B

Solution:

Concept:

Scalar multiplication and subtraction of matrices are performed element-wise.

Explanation:

Given

A = \begin{pmatrix} 2 & 3 \\ 4 & 5 \end{pmatrix}

and

B = \begin{pmatrix} 1 & 5 \\ 6 & 7 \end{pmatrix}

First, compute

3A

by multiplying every entry of

A

by 3:

3A = \begin{pmatrix} 6 & 9 \\ 12 & 15 \end{pmatrix}

Then subtract

B

3A - B = \begin{pmatrix} 6-1 & 9-5 \\ 12-6 & 15-7 \end{pmatrix} = \begin{pmatrix} 5 & 4 \\ 6 & 8 \end{pmatrix}

Answer:

\begin{pmatrix} 5 & 4 \\ 6 & 8 \end{pmatrix}

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