Question

Qual o resultado?
A) (4x-1)²
B) ((2a-5b)²
Ç) (x+1)(x-1)
D) (a+5)(a-5)
E) (3b+7)(3b-7)
F) (x²+2)(x²-7)

Answer 1

a
( 4x - 1)² = [ (4x)²  - 2.4x.1  +( 1)² ]
16x² - 8x + 1 ****
b
( 2a - 5b)²  = [ (2a)²  - 2.2a.5b + ( 5b)²]  =
4a² - 20ab + 25b² ***
c
( x + 1) ( x - 1) =  [ (x²)  - ( 1)²  ]  = x² - 1 ****
d
( a + 5) ( a - 5)  = [ (a)²  - ( 5)² ] = a² - 25 ****
e
( 3b + 7 ) ( 3b - 7 ) = [ (3b)²  + 2 .3b.7 + ( 7 )² ] = 9b² +42b + 49 ***
f
(x² + 2)( x²  - 7 )  = x⁴ - 7x² + 2x² - 14 = x⁴ - 5x²  - 14 ***