Question

aplicando as regras dos produtos notaveis,calcule:

a) (7a+1).(7a-1)
b) (2x+9x)²
c) (6x-y)²
d) (a³+6y²)²

Answer 1

(7a + 1)(7a - 1)
= 49a² - 1

(2x + 9x)²
= (11x)²
= 121x²

(6x - y)²
= 36x² - 12xy + y²

(a³ + 6y²)²
= a⁶ + 12a³y² + 36y⁴

Answer 2

a)
= (7a + 1).(7a - 1)
= 7a.7a - 1.7a + 1.7a + 1.(-1)
= 49a² - 7a + 7a - 1
= 49a² - 1
-----------------------------------------
b)
= (2x + 9y)²
= 4x² + 2.2x.9y + 81y² 
= 4x² + 36xy + 81y²
----------------------------------------------------
c)
= (6x - y)²
= (6x)² - 2.6x.y + (-y)²
= 36x² - 2.6x.y + y²
= 36x² - 12xy + y²
-------------------------------------------------------
d)
= (a³ + 6y²)²
= (a³)² + 2.a³.6y² + (6y²)²
= a⁶ + 2.a³.6y² + 36y⁴
= a⁶ + 12a³y² + 36y⁴