alleryStart learning →For a 3x3 identity matrix I, det(I) equals:
- 0
- 1
- 3
- 9
Show answer and solution
Correct answer: B. 1
Determinant of any identity matrix is 1. (Since I is diagonal with all diagonal entries 1, det = 1 × 1 × 1 = 1.)
Indian Navy SSR Matrices — practice questions
Explore 29 free Matrices questions in Indian Navy SSR Mathematics. Open each question or exercise to read its content, reference answers and available explanation.
Practise Matrices with Quill →Matrices questions and exercises with answers
Showing questions 1–29 of 29.
For a 3x3 identity matrix I, det(I) equals:Read the answer and worked solution →The element a_23 of a matrix is located at:Read the answer and worked solution →For an n × n matrix A, A is invertible if and only if:Read the answer and worked solution →Inverse of [[2,0],[0,3]]:Read the answer and worked solution →Match each kind of matrix to its conditionRead the answer and worked solution →Sort each matrix by its shapeRead the answer and worked solution →Tap every matrix that must be squareRead the answer and worked solution →Complete the definition of a matrixRead the answer and worked solution →When is a product defined?Read the answer and worked solution →True or false: transposesRead the answer and worked solution →Symmetric or skew symmetric?Read the answer and worked solution →True or false: matrix algebraRead the answer and worked solution →Complete the equality conditionRead the answer and worked solution →Order the steps: is AB defined, and what order is it?Read the answer and worked solution →Spot the one that does not belongRead the answer and worked solution →Special square matricesRead the answer and worked solution →Assertion and reasonRead the answer and worked solution →Two are true, one is notRead the answer and worked solution →Three of these are wrong. Find the one that holds.Read the answer and worked solution →Tap every statement true of the identity matrixRead the answer and worked solution →Flip and pair: notation with meaningRead the answer and worked solution →True or false: inversesRead the answer and worked solution →Complete the scalar multiplication rulesRead the answer and worked solution →Which operation needs matching orders?Read the answer and worked solution →Spot the odd one outRead the answer and worked solution →Reading the definitions backRead the answer and worked solution →Assertion and reason: structureRead the answer and worked solution →Order the steps: test whether A is symmetricRead the answer and worked solution →True or false: orders and shapesRead the answer and worked solution →
Worked practice questions
The element a_23 of a matrix is located at:
- Row 2, column 3
- Row 3, column 2
- Diagonal
- Top-right corner
Show answer and solution
Correct answer: A. Row 2, column 3
By convention, a_ij denotes element in row i and column j.
**So a_23 is row 2, column 3.**
For an n × n matrix A, A is invertible if and only if:
- det(A) = 0
- det(A) ≠ 0
- Aᵀ = A
- Tr(A) = 0
Show answer and solution
Correct answer: B. det(A) ≠ 0
A is invertible iff det(A) ≠ 0 (nonsingular).
If det = 0, the matrix is called singular and has no inverse.
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