1
COMEDK 2020
MCQ (Single Correct Answer)
+1
-0

If $$A = \left[ {\matrix{ 1 & { - 1} & 1 \cr 2 & 1 & { - 3} \cr 1 & 1 & 1 \cr } } \right],10B = \left[ {\matrix{ 4 & 2 & 2 \cr { - 5} & 0 & \alpha \cr 1 & { - 2} & 3 \cr } } \right]$$ and B is the inverse of A, then the value of $$\alpha$$ is

A
0
B
2
C
4
D
5
2
COMEDK 2020
MCQ (Single Correct Answer)
+1
-0

If $$A = \left[ {\matrix{ 0 & x & {16} \cr x & 5 & 7 \cr 0 & 9 & x \cr } } \right]$$ is singular, then the possible values of x are

A
$$0,1,-1$$
B
$$0,+12,-12$$
C
$$0,5,-5$$
D
$$0,4,-4$$
3
COMEDK 2020
MCQ (Single Correct Answer)
+1
-0

If $$A = \left[ {\matrix{ 1 & { - 2} & 2 \cr 0 & 2 & { - 3} \cr 3 & { - 2} & 4 \cr } } \right]$$, then A . adj (A) is equal to

A
$$\left[ {\matrix{ 5 & 0 & 0 \cr 0 & 5 & 0 \cr 0 & 0 & 5 \cr } } \right]$$
B
$$\left[ {\matrix{ 5 & 1 & 1 \cr 1 & 5 & 1 \cr 1 & 1 & 5 \cr } } \right]$$
C
$$\left[ {\matrix{ 0 & 0 & 0 \cr 0 & 0 & 0 \cr 0 & 0 & 0 \cr } } \right]$$
D
$$\left[ {\matrix{ 8 & 0 & 0 \cr 0 & 8 & 0 \cr 0 & 0 & 8 \cr } } \right]$$
4
COMEDK 2020
MCQ (Single Correct Answer)
+1
-0

If $$f:R \to R$$ is defined by $$f(x) = |x|$$, then

A
$${f^{ - 1}}(x) = {1 \over {|x|}}$$
B
$${f^{ - 1}}(x) = - x$$
C
$${f^{ - 1}}(x) = {1 \over x}$$
D
The function $${f^{ - 1}}(x)$$ does not exist.
EXAM MAP