Respostas

2014-08-03T20:47:26-03:00
(5x - 1).(5x + 1)
25x² + 5x - 5x - 1
25x² - 1

(a + b).(a + b)
a² + ab + ab + b²
a² + 2ab+ b²

(2x² - 3x - 6).(5x - 2)
10x³ - 6x² - 15x² + 6x - 30x + 12
10x³ - 21x² - 24x + 12

(2a + 3/5b).(a - 1/2b)
2a² - 2a/2b + 3a/5b - 3/10b²
2a² + a/b - 3/10b²