Question

calcule cada produto abaixo :
a) (4 + √2 ) x (4 - √2)
b) (2√7 - 3 )²
c) (√3 + 5 ) ²

Answer 1

$a) \ (4 + \sqrt2 ) * (4 - \sqrt2)= 16-4\sqrt2+4\sqrt2-2=14\\ \\b) \ (2\sqrt7 - 3 )^2=28-12\sqrt7+9=37-12\sqrt7\\ \\c) \ (\sqrt3 + 5 ) ^2 =3+10\sqrt3+25=28+10\sqrt3$

Answer 2

a) (4 + √2 ) x (4 - √2)  = 4² - (√2)² = 16 - 2 = 14
b) (2√7 - 3 )² = (2√7)² -12√7 (-3)² = 28 - 12√7 +9 = 37 - 12√7
c) (√3 + 5 ) ² = (√3)²  + 10√3 + 5² = 3 + 10√3 +25 = 28 + 10√3

Okais !!