No.1 For this determinant, find the minors and algebraic complements. Calculate the determinant: a) by expanding it on the elements i of the line; b) expanding it into the elements of the j column; c) having previously obtained zeros in the i line. i = 4; j = 1.

No.2 Two matrices A and B are given. Find: a) AB; b) BA; c) AA; d) AA⁻¹; d) А⁻¹А