MCQ
Assertion (A) : $B=\left[\begin{array}{llll}-\frac{1}{2} & \sqrt{5} & 2 & 3\end{array}\right]_{1 \times 4}$ is a row matrix.
Reason (R): If $B=\left[b_{i j}\right]_{1 \times n}$ is a row matrix, then its order is $n \times 1$.
  • Both (A) and (R) are true and (R) is the correct explanation of (A).
  • B
    Both (A) and (R) are true but (R) is not the correct explanation of (A).
  • C
    (A) is true but (R) is false.
  • D
    (A) is false but (R) is true.

Answer

Correct option: A.
Both (A) and (R) are true and (R) is the correct explanation of (A).
(a) : $B=\left[\begin{array}{llll}-\frac{1}{2} & \sqrt{5} & 2 & 3\end{array}\right]_{1 \times 4}$ is a row matrix. In general, $B=\left[b_{i j}\right]_{1 \times n}$ is a row matrix of order $1 \times n$.

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