1
NDA Mathematics 14th September 2025
MCQ (Single Correct Answer)
+2.5
-0.833
Change Language

Consider the following statements:

Statement-l: If X is an nn matrix, then det(mX) = $m ^ n$ det(X), where m is a scalar.

Statement-II: If Y is a matrix obtained from X by multiplying any row or column by a scalar m, then det (Y) = m det (X).

Which one of the following is correct in respect of the above statements?

1
Both Statement-1 and Statement-II are correct and Statement-II explains Statement-I
2
 Both Statement-I and Statement-II are correct but Statement-II does not explain Statement-1
3
Statement-I is correct but Statement-II is not correct
4
 Statement-I is not correct but Statement-II is correct
2
NDA Mathematics 14th September 2025
MCQ (Single Correct Answer)
+2.5
-0.833
Change Language

Consider the following statements about

the matrix $M=\left[\begin{matrix}71&23&48\\ 57&28&29\\ 65&17&48\end{matrix}\right]$ 

Statement-I: The inverse of M does not exist.

Statement-II: M is non-singular.

Which one of the following is correct in respect of the above statements?

1
Both Statement-I and Statement-II are correct and Statement-II explains Statement-I
2
Both Statement-I and Statement-II are correct but Statement-II does not explain Statement-I
3
Statement-I is correct but Statement-II is not correct
4
 Statement-I is not correct but Statement-II is correct
3
NDA Mathematics 13 April 2025
MCQ (Single Correct Answer)
+2.5
-0.833
Change Language

If $\Delta = \begin{vmatrix} a & b & c \\ d & e & f \\ g & h & i \end{vmatrix} $ 

and A, B, C, D, G are the cofactors of the elements a, b, c, d, g respectively, then what is equal to?

A
0
B
1
C
Δ
D
Δ
4
NDA Mathematics 13 April 2025
MCQ (Single Correct Answer)
+2.5
-0.833
Change Language

. Consider the following statements in respect of the determinant 

$ \Delta = \begin{vmatrix} k(k+2) & 2k+1 & 1 \\ 2k+1 & k+2 & 1 \\ 3 & 3 & 1 \end{vmatrix} $

I. Δ is positive if .

II. Δ is negative if .

III. Δ is zero if .

How many of the statements given above are correct?

A
None 
B
One 
C
Two 
D
All three