1
KCET 2021
MCQ (Single Correct Answer)
+1
-0

$$\cos \left[\cot ^{-1}(-\sqrt{3})+\frac{\pi}{6}\right]$$ is equal to

A
0
B
1
C
$$\frac{1}{\sqrt{2}}$$
D
$$-1$$
2
KCET 2021
MCQ (Single Correct Answer)
+1
-0

$$\tan ^{-1}\left[\frac{1}{\sqrt{3}} \sin \frac{5 \pi}{2}\right] \sin ^{-1}\left[\cos \left(\sin ^{-} \frac{\sqrt{3}}{2}\right)\right]$$ is equal to

A
$$\left(\frac{\pi}{6}\right)^2$$
B
$$\frac{\pi}{6}$$
C
$$\frac{\pi}{3}$$
D
$$\pi$$
3
KCET 2021
MCQ (Single Correct Answer)
+1
-0

If $$A=\left[\begin{array}{ccc}1 & -2 & 1 \\ 2 & 1 & 3\end{array}\right]$$

$$ B=\left[\begin{array}{ll}2 & 1 \\ 3 & 2 \\ 1 & 1\end{array}\right]$$, then $$(A B)^{\prime}$$ is equal to

A
$$\left[\begin{array}{cc}-3 & -2 \\ 10 & 7\end{array}\right]$$
B
$$\left[\begin{array}{cc}-3 & 10 \\ -2 & 7\end{array}\right]$$
C
$$\left[\begin{array}{ll}-3 & 7 \\ 10 & 2\end{array}\right]$$
D
$$\left[\begin{array}{cc}-3 & 7 \\ 10 & -2\end{array}\right]$$
4
KCET 2021
MCQ (Single Correct Answer)
+1
-0

Let $$M$$ be $$2 \times 2$$ symmetric matrix with integer entries, then $$M$$ is invertible if

A
the first column of $$M$$ is the transpose of second row of $$M$$.
B
the second row of $$M$$ is the transpose of first column of $$M$$.
C
$$M$$ is diagonal matrix with non-zero entries in the principal diagonal.
D
The product of entries in the principal diagonal of $$M$$ is the product of entries in the other diagonal.