Question

alguém pra mim ajudar:)?​

Answer 1

Resposta:

$D)~~\dfrac{\sqrt{2} .(\sqrt{2} -1)}{(\sqrt{2} +1)(\sqrt{2} -1)}=\dfrac{\sqrt{4} -\sqrt{2} }{(\sqrt{2} )^2-1^2}=\dfrac{2-\sqrt{2} }{2-1}=\dfrac{2-\sqrt{2} }{1}=\boxed{2-\sqrt{2} }$

$E)~~\dfrac{1.(\sqrt{5} -\sqrt{2}) }{(\sqrt{5}+\sqrt{2} )(\sqrt{5} -\sqrt{2} )}=\dfrac{\sqrt{5} -\sqrt{2} }{(\sqrt{5} )^2-(\sqrt{2} )^2}=\dfrac{\sqrt{5} -\sqrt{2} }{5-2}=\boxed{\dfrac{\sqrt{5} -\sqrt{2} }{3}}$