Zaymiey

📐 Mathematics  ·  Matrices  ·  JEE

If A has order m x n and B has order n x p, then AB has order:

Answer: m x p.

  • A n x n
  • B m x p
  • C m x n
  • D n x p

Correct answer: B. m x p

Explanation: For AB to exist, columns of A must equal rows of B. The resulting matrix has order m x p.

Matrix A (3 rows x 3 columns)a11a12a13a21a22a23a31a32a33column 1column 2column 3row 1row 2row 3

Element aij of matrix A sits at the intersection of row i and column j.

Concept context

Matrix operations, determinants, inverses, and solving linear systems

Read the full Matrices notes →