MCQ
The matrix $\text{A}=\begin{bmatrix}1&0&0\\0&2&0\\0&0&4\end{bmatrix}$ is:
  • A
    Identity matrix.
  • B
    Symmetric matrix.
  • C
    Skew-symmetric matrix.
  • Diagonal matrix.

Answer

Correct option: D.
Diagonal matrix.
A matrix is called Diagonal matrix if all the elements, except those in the leading diagonal, are zero.

Need a full question paper?

Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.

Start Generating Free

Similar questions

Let $\vec a = 2\hat i + \hat j - 2\hat k,\,\vec b = \hat i + \hat j$ . If $\vec c$ is a vector such that $\vec a.\vec c + 2\left| {\vec c} \right| = 0$ and $\left| {\vec c - \vec a} \right| = \sqrt {14} $ and angle between $\vec a \times \vec b$ and $\vec c$ is $30^o$ , then $\left| {\left( {\vec a \times \vec b} \right) \times \vec c} \right|$ is
A line passes through the point $A (5,-2.4)$ and it is parallel to the vector $(2 \hat{i}-\hat{j}+3 \hat{k})$. The vector equation of the line is
Let $\vec{a}=2 \hat{i}+3 \hat{j}+4 \hat{k}, \vec{b}=2 \hat{i}-2 \hat{j}-2 \hat{k}$ and $\overrightarrow{ c }=-\hat{ i }+4 \hat{ j }+3 \hat{ k }$. If $\overrightarrow{ d }$ is a vector perpendicular to both $\vec{b}$ and $\overrightarrow{ c }$ and $\overrightarrow{ a } \cdot \overrightarrow{ d }=18$, Then $|\overrightarrow{ a } \times \overrightarrow{ d }|^2$ is equal to $..........$.
Which of the given qualities is a vector:
Four numbers are chosen at random ( without replacement ) from the set $\{1,2,3,..,20\}$

Statement $-1 :$ The probability that the chosen numbers when arranged in some order will form an $A.P.$ is $\frac{1}{{85}}$ . 

Statement $-2 :$ If the four chosen numbers form an $A.P.$, then the set of all possible values of common difference is $\left( { \pm 1, \pm 2, \pm 3, \pm 4, \pm 5} \right)$ છે.

The function $L(x) = \int_1^x {\frac{{dt}}{t}} $ satisfies the equation
The function $f(x)=x^2 e^{-x}$ is monotonic increasing when :
$r \times a = b \times a;\,\,r \times b = a \times b;\,\,a \ne 0;\,\,b \ne 0;\,\,a \ne \lambda b,\,\,$ $a $ is not perpendicular to $ b,$  then $r = $
$\int_{ - \pi /2}^{\pi /2} {\sqrt {\frac{1}{2}(1 - \cos 2x)} } \,dx = $
If $u = \sqrt {{a^2}{{\cos }^2}\theta + {b^2}{{\sin }^2}\theta } + \sqrt {{a^2}{{\sin }^2}\theta + {b^2}{{\cos }^2}\theta } $, then difference between the maximum and minimum values of ${u^2}$ is given by