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Let A, B, and C be non-singular 2x2 matrices, I the 2x2 identity matrix and k a scalar. The following statements are incorrect. For each statement, write down the correct version of the right hand side.

(a) (A+B)2 = A2+2AB+B2

(b) (A-kI)3 = A3-3kA2+3k2A-k3

(c) CA=B C=B/A

Please show logical and detailed work.