Let AAA, BBB and CCC be real square matrices of the same size, and suppose that AAA is invertible. Prove that if (A−B)C=BA−1(A-B)C = BA^{-1}(A−B)C=BA−1, then C(A−B)=A−1BC(A-B) = A^{-1}BC(A−B)=A−1B.
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