1
COMEDK 2023 Morning Shift
MCQ (Single Correct Answer)
+1
-0

If $$A=\left[\begin{array}{cc}k+1 & 2 \\ 4 & k-1\end{array}\right]$$ is a singular matrix, then possible values of $$\mathrm{k}$$ are

A
$$\pm 1$$
B
$$\pm 2$$
C
$$\pm 3$$
D
$$\pm 4$$
2
COMEDK 2023 Morning Shift
MCQ (Single Correct Answer)
+1
-0

The angle between the vectors $$\mathbf{a}=\hat{\mathbf{i}}+2 \hat{\mathbf{j}}+2 \hat{\mathbf{k}}$$ and $$\mathbf{b}=\hat{\mathbf{i}}+2 \hat{\mathbf{j}}-2 \hat{\mathbf{k}}$$ is

A
$$\sin ^{-1}(1 / 9)$$
B
$$\sin ^{-1}(8 / 9)$$
C
$$\cos ^{-1}(8 / 9)$$
D
$$\cos ^{-1}(1 / 9)$$
3
COMEDK 2023 Morning Shift
MCQ (Single Correct Answer)
+1
-0

If the vectors $$\mathbf{a}=2 \hat{\mathbf{i}}-3 \hat{\mathbf{j}}+4 \hat{\mathbf{k}} ; \mathbf{b}=\hat{\mathbf{i}}+2 \hat{\mathbf{j}}-\hat{\mathbf{k}}$$ and $$\mathbf{c}=m \hat{\mathbf{i}}-\hat{\mathbf{j}}+2 \hat{\mathbf{k}}$$ are coplanar, then the value of $$m$$ is

A
$$\frac{5}{8}$$
B
$$\frac{8}{5}$$
C
$$\frac{-7}{4}$$
D
$$\frac{2}{3}$$
4
COMEDK 2023 Morning Shift
MCQ (Single Correct Answer)
+1
-0

The maximum value of $$Z=12 x+13 y$$, subject to constraints $$x \geq 0, y \geq 0, x+y \leq 5$$ and $$3 x+y \leq 9$$ is

A
63
B
65
C
60
D
117
EXAM MAP