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If A is a square matrix such that A^(3)...

If A is a square matrix such that `A^(3) =I` then the value of `A^(-1) ` is equal to

A

I

B

A

C

`A^(2) `

D

none of these

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The correct Answer is:
To solve the problem, we need to find the value of \( A^{-1} \) given that \( A^3 = I \), where \( I \) is the identity matrix. ### Step-by-Step Solution: 1. **Understanding the Given Information**: We are given that \( A^3 = I \). This means that when the matrix \( A \) is multiplied by itself three times, the result is the identity matrix. 2. **Rewriting the Expression**: We can express \( A^3 \) as: \[ A^3 = A \times A \times A \] Since \( A^3 = I \), we can write: \[ A \times A \times A = I \] 3. **Finding the Inverse**: We want to find \( A^{-1} \). From the property of inverses, we know that if \( A^3 = I \), we can manipulate this equation to find \( A^{-1} \). We can rearrange \( A^3 = I \) as follows: \[ A^3 \times A^{-1} = I \times A^{-1} \] This simplifies to: \[ A^2 = A^{-1} \] Thus, we have: \[ A^{-1} = A^2 \] 4. **Conclusion**: Therefore, the value of \( A^{-1} \) is: \[ A^{-1} = A^2 \] ### Final Answer: \[ A^{-1} = A^2 \]
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