AIEEE,IIT JEE MATHS-ALGEBRA --I online Test

The cofactor of the element '4' in the determinant
____.
4
10
– 10
– 4


this system of equations has ____.
Infinite solution
No solution
Unique solution
None of the above
The value of
if
is ____.
0
1
– 1
None of the above
If
and

then the value of
is ____.
1/3
½
1
2
In a skew symmetric matrix, the diagonal elements are all ____.
Different from each other
Zero
One
None of the above
If I is a unit matrix, then 3I is ____.
A unit matrix
A triangular matrix
A scalar matrix
None of the above
The set of matrices
forms a group under matrix multiplication as the binary operation. The identity element in it is ____.
Square matrices of the type
form a group under the usual matrix multiplication. The identity of the group is ____.
The set
under matrix multiplication forms ____.
An abelian group
Non-abelian group
Cyclic group
None of the above
If M is a group under multiplication and M denotes set of all
non-singular matrices of the form
where a, b, c, d are real numbers, then the inverse of
is ____.