(x − 4)(x − 2) − 3(x+4)(4−x) = x^2 - 2x - 4x + 8 - 12(4 - x) = x^2 - 6x + 8 - 48 + 12x = x^2 + 6x - 40
7a^6 / a^3 = 7a^(6-3) = 7a^3
(6 choose 3) = 6! / (3! * (6-3)!) = 20.
(x − 4)(x − 2) − 3(x+4)(4−x) = x^2 - 2x - 4x + 8 - 12(4 - x) = x^2 - 6x + 8 - 48 + 12x = x^2 + 6x - 40
7a^6 / a^3 = 7a^(6-3) = 7a^3
(6 choose 3) = 6! / (3! * (6-3)!) = 20.