Question

Efetue as multiplicações:

a) (a+1).(a+2)
b) (n+5).(n-3)
c) (4x²-3).(x+1)
d) (3a-b).( 3a+b)
e) (3m-5).( 2m-1)
f) (x-7)²
g) (x+6).(x-6)
h) (a+6).( 3a-2)

Answer 1

a)(a + 1 ) . (a + 2 ) = a² + 2 a + a + 2 = a² + 3 a + 2
b)(n + 5) (n - 3 ) = n²- 3 n + 5 n - 15 = n² + 2 n - 15
c)(4 x² - 3 ) (x + 1 ) = 4 x³  + 4 x² - 3 x - 3 
d)(3 a - b) (3 a + b)9 a² + 3 a b - 3 a b  - b² = 9 a² - b²
e) (3 m - 5 ) (2 m - 1 ) = 6 m² - 3 m - 10 m + 5 = 6 m² - 13 m  + 5
f)(x - 7 )² = x² - 2 . x . 7 + 7² = x² - 14 x  + 49
g)(x + 6 ) (x - 6 ) = x² - 6 x + 6 x  - 36 = x² - 36
h) (a + 6 ) ( 3 a - 2 ) = 3 a²  - 2 a + 18 a - 12 = 3 a² + 16 a - 12