Решите (2x-4) (3x+7) x-2

Question

Решите (2x-4) (3x+7) x-2

Answer 1

(2х-4)(3х+7) = 6х² + 14х - 12х -28 = 6х² +2х -28
при х = 2
6×2² +2×2 -28 = 6×4 +4 -28 = 24 +4 -28 = 28 -28 = 0
при х = -2
6×(-2)² +2(-2) -28 = 6×4 -4 -28 = 24 -4 -28 = 24 -32 = -8