Question

(UE-CE) O valor da expressão 12.[(√2)^(-2)- (√3)^(-2)] é igual a:



A)2    B)3    C)√2    D)√3    E)NDA 

Answer 1

$12.[( \sqrt{2})^{-2} -( \sqrt{3} )^{-2}]$

$12.[ \sqrt{2^{-2}} - \sqrt{3^{-2}} ]\\12.[2^{- \frac{2}{2} }-3^{- \frac{2}{2} }]$

$12.[2^{-1}-3^{-1}]\\12.[ \frac{1}{2} - \frac{1}{3} ]$

$12.[ \frac{1}{6} ]$

$\frac{12}{6}$

$\boxed{2}$