Respostas

2014-06-04T23:10:49-03:00
A)( a + 1 )³=

( a + 1 ) ( a + 1 ) ( a + 1 ) =
a² + a + a + 1 ( a + 1 ) =
a² + 2a + 1 ( a + 1 ) =
a³ + 2a² + a + a² + 2a + 1 =
a³ + 3a² + 3a + 1


b) (2b - 4) ³
(2b - 4) (2b - 4) (2b - 4)
4b² - 8b - 8b + 16 (2b - 4)
4b² - 16b + 16 (2b - 4)
8b³ - 32b² +32b - 16b² + 64b - 64
8b³ - 48b² + 98b - 64