1
NDA Mathematics 21 April 2024
MCQ (Single Correct Answer)
+2.5
-0.83
Consider the following statements in respect of two non-singular matrices $A$ and $B$ of the same order $n$:
- 1.$adj(AB) = (adjA)(adjB)$
- 2. $adj(AB) = adj(BA)$
- 3. $(AB) adj(AB) - |AB| I_n$ is a null matrix of order $n$
How many of the above statements are correct?
2
NDA Mathematics 21 April 2024
MCQ (Single Correct Answer)
+2.5
-0.83
Consider the following statements in respect of a non-singular matrix $A$ of order $n$:
1. $A(\text{adj}A^T) = A(\text{adj}A)^T$
2. If $A^2 = A$, then $A$ is identity matrix of order $n$
3. If $A^3 = A$, then $A$ is identity matrix of order $n$
Which of the statements given above are correct?
3
NDA Mathematics 21 April 2024
MCQ (Single Correct Answer)
+2.5
-0.83
Consider the following statements in respect of a skew-symmetric matrix $A$ of order $3$:
1. All diagonal elements are zero.
2. The sum of all the diagonal elements of the matrix is zero.
3. $A$ is orthogonal matrix.
Which of the statements given above are correct?
4
NDA Mathematics 21 April 2024
MCQ (Single Correct Answer)
+2.5
-0.83
If $A=\left[\begin{array}{ccc}\sin 2 \theta & 2 \sin ^2 \theta-1 & 0 \\ \cos 2 \theta & 2 \sin \theta \cos \theta & 0 \\ 0 & 0 & 1\end{array}\right]$, then which of the following statements is/are correct?
1. $A^{-1}=\operatorname{adj} A$
2. A is skew-symmetric matrix
3. $A^{-1}=A^T$
Select the correct answer using the code given below :
1. $A^{-1}=\operatorname{adj} A$
2. A is skew-symmetric matrix
3. $A^{-1}=A^T$
Select the correct answer using the code given below :
Questions Asked from Matrices (Marks 2.5)
Number in Brackets after Paper Indicates No. of Questions
NDA Subjects
Mathematics
Algebra
Sets, Relations and Functions Logarithms Quadratic Equations and Inequalities Sequence And Series Binomial Theorem Matrices Determinants Permutations and Combinations Probability Complex Numbers Vector Algebra Three Dimensional Geometry Statistics
Trigonometry
Trigonometric Angles and Equations Inverse Trigonometric Function Height and Distance Properties of Triangles
Coordinate Geometry
Calculus
English
General Studies