Рябушко А.П. АЗ_1_2

Matrices and operations on them
No. 1. Matrices A and B are given. Find: A B; 2A; A-3B.
No. 2. Matrices A and B are given. Find: AB; 2A; VA.
№ 3. For matrix A, find all square matrices B that commute (commuting) with it. Check the validity of the equality AB=BA.
No. 4. Matrices A are given; B and C. Find: A(BC); (AB)C and show that A(BC) = (AB)C.

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