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State with reason, whether the following are true of false. A, B and C are matrices of order `2 xx 2`.
`(A-B)^2=A^2-2A. B+B^2`.

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To determine whether the statement \((A - B)^2 = A^2 - 2AB + B^2\) is true or false for matrices \(A\), \(B\), and \(C\) of order \(2 \times 2\), we will expand the left-hand side and compare it with the right-hand side. ### Step-by-Step Solution: 1. **Expand the Left-Hand Side**: \[ (A - B)^2 = (A - B)(A - B) \] Using the distributive property (also known as the FOIL method for binomials), we can expand this: \[ (A - B)(A - B) = A \cdot A - A \cdot B - B \cdot A + B \cdot B \] This simplifies to: \[ = A^2 - AB - BA + B^2 \] 2. **Compare with the Right-Hand Side**: The right-hand side of the equation is: \[ A^2 - 2AB + B^2 \] We can rewrite this as: \[ A^2 - AB - AB + B^2 \] 3. **Analyze the Two Expressions**: From our expansion, we have: \[ (A - B)^2 = A^2 - AB - BA + B^2 \] And from the right-hand side, we have: \[ A^2 - 2AB + B^2 = A^2 - AB - AB + B^2 \] For the two expressions to be equal, we need: \[ -AB - BA = -2AB \] Rearranging gives us: \[ -AB - BA + 2AB = 0 \implies AB - BA = 0 \] This means that \(AB = BA\), which is only true if \(A\) and \(B\) commute. 4. **Conclusion**: Since \(A\) and \(B\) are arbitrary \(2 \times 2\) matrices, they do not necessarily commute. Therefore, the original statement is **false**. ### Final Answer: The statement \((A - B)^2 = A^2 - 2AB + B^2\) is **false** because the laws of algebra for factorization and expansion do not hold for matrices unless the matrices commute.
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