Matrices & Determinants

JKSSB Panchayat Account Assistant · Mathematics/Statistics · 16 practice questions with answers and explanations: 4 Easy, 6 Medium, 6 Hard.

Sample questions

Sample Easy question 1

What is the order of a matrix with 2 rows and 3 columns?

  1. 6×1
  2. 2×2
  3. 2×3
  4. 3×2
Show answer

Answer: C. Matrix order is stated as rows × columns: 2×3.

Sample Medium question 2

The product [[1, 2], [0, 1]] × [[1, 0], [3, 1]] is:

  1. [[2, 2], [3, 2]]
  2. [[7, 2], [3, 1]]
  3. [[1, 2], [3, 7]]
  4. [[1, 0], [0, 1]]
Show answer

Answer: B. Row 1: (1·1 + 2·3, 1·0 + 2·1) = (7, 2). Row 2: (0·1 + 1·3, 0·0 + 1·1) = (3, 1).

Sample Hard question 3

A square matrix A for which Aᵀ = −A is called:

  1. Orthogonal
  2. Singular
  3. Symmetric
  4. Skew-symmetric
Show answer

Answer: D. Skew-symmetric matrices satisfy Aᵀ = −A (so their diagonal entries are all zero); symmetric ones satisfy Aᵀ = A.

More Mathematics/Statistics topics for JKSSB Panchayat Account Assistant

Related articles