câu 9, 10, 17, 19, 23 ạ
(3x + 5)(2x - 7)
= 6x^2 + 10x - 21x - 35
= 6x^2 - 11x - 35
(- 5x + 2)(- 3x - 4)
= 15x^2 - 6x + 20x - 8
= 15x^2 + 16x - 8
....
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(3x + 5)(2x - 7)
= 6x^2 + 10x - 21x - 35
= 6x^2 - 11x - 35
(- 5x + 2)(- 3x - 4)
= 15x^2 - 6x + 20x - 8
= 15x^2 + 16x - 8
....