... thức:a) (6 x + 1) 2 + (6 x – 1) 2 – 2 (1 + 6x )( 6 x – 1) = (6 x + 1 – 6x + 1) 2 = 4b) 3(2 2 + 1) (2 4 + 1) (2 8 + 1) (2 16 + 1) = (2 2 – 1) (2 2 + 1) (2 4 + 1) (2 8 + 1) (2 16 + 1) = (2 4 – 1) ( ... 1) – x3(x2 – 1) + (x2 – 1) = (x2 – 1) (x7 – x4 – x3 + 1) = (x2 – 1) [ (x7 – x3 ) – (x4 – 1) ] = (x2 – 1) (x4 – 1) (x3 – 1) = (x – 1) (x + 1) (x2 + 1) (x2 – 1) (x – 1) (x2 ... 3z)(x – 2y + 3z) = [(x + 3z) + 2y] [(x + 3z) – 2y] = (x + 3z)2 – (2 y)2 c) (x – 1) (x2 – x + 1) (x + 1) (x2 + x + 1) = (x – 1) (x2 + x + 1) (x + 1) (x2 – x + 1) = (x3 – 1) (x3 + 1) =...