Question

Fatorando ( a + b )² - 4c² obtém-se : 
a) ( a + b - 2c)(a + b - 2c) 
b) ( a + b + 2c)(a + b - 2c) 
c) ( a + b + c )(a + b - 2 ) 
d) ( a + b -c )( a + b + 2 ) 
e) ( a + b + 4 )(a + b - c ) 

Answer 1

$( a + b )^2 - 4c^2=a^2+2ab+b^2-4c^2 = (a+b-2 c) (a+b+2 c)$