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GATE 2020 ME (ME1) – Question 11

Engineering Mathematics · Linear Algebra: Matrix algebra, systems of linear equations, eigen values and eigen vectors · 1 mark · Multiple choice

Multiplication of real-valued square matrices of the same dimension is ______.

  1. associative
  2. commutative
  3. always positive definite
  4. not always possible to compute

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Show answer and explanation

Correct answer: (A) associative

Explanation

For conformable matrices, (AB)C=A(BC), so multiplication is associative. Generally AB differs from BA. A product need not be symmetric or positive definite. Equal square dimensions ensure the product exists. **Answer: A.**