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A and B are two matrices such that the order of A is 3 × 4 , if A ′ B and B A ′ are both defined, then

Options

  1. Aorder of B ′ is 3 × 4
  2. Border of B ′ A is 4 × 4
  3. Corder of B ′ A is 3 × 3
  4. DB ′ A is not defined

Correct answer

B. order of B ′ A is 4 × 4

Step-by-step solution

Let, order of B is m × n ∵ A ′ B is defined so m = 3 ∴ B A ′ is defined so n = 4 ⇒ order of B is 3 × 4 ∴ order of B ′ A is 4 × 4

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