Question

10- Sendo x = √7 + 1 e y = √7– 1 , determine :
a) X + y b) x – y c) x . y
AJUDA

Answer 1

Resposta:

Explicação passo-a-passo:

a)

$x+y\\\\= \sqrt{7} +1 +(\sqrt{7}-1)\\\\= \sqrt{7} +1 +\sqrt{7}-1\\\\= 2\sqrt{7}$

b)

$x-y\\\\= \sqrt{7} +1 -(\sqrt{7}-1)\\\\= \sqrt{7} +1 -\sqrt{7}+1\\\\= 2$

c)

$x.y\\\\= (\sqrt{7} +1 ).(\sqrt{7}-1)\\\\= (\sqrt{7})^2+ \sqrt{7}-\sqrt{7}-1\\\\= 7-1\\\\=6$