Consider the following statements: 1. If A′ = A; then A is a singular matrix, where A′ is the transpose of A. 2. If A is a square matrix such that A3 = I, then A is non-singular. Which of the statements given above is/are correct ?
Consider the following statements: 1. If A′ = A; then A is a singular matrix, where A′ is the transpose of A. 2. If A is a square matrix such that A3 = I, then A is non-singular. Which of the statements given above is/are correct ? Correct Answer 2 only
Concept:
A matrix is singular if and only if its determinant is zero.
Calculation:
If A′ = A; where A′ is the transpose of A then |A| = |A'|
But it is not necessary that |A| = 0, so A is not a singular matrix.
Hence, Statement 1 is wrong.
Given, A3 = I
Taking determinants both sides, we get
⇒|A3 | = |I| = 1
⇒ |A| = 1
Here, |A|≠ 0 so, A is a non-singular matrix
Hence, option (2) is correct.
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Feb 20, 2025