Question

Giúp mình câu 10 ạ!

Answer 1

d: \(\dfrac{\sqrt{a+3}+\sqrt{a-3}}{\sqrt{a+3}-\sqrt{a-3}}\)

\(=\dfrac{a+3+a-3+2\sqrt{a^2-9}}{a+3-a+3}\)

\(=\dfrac{2a+2\sqrt{a^2-9}}{6}\)

\(=\dfrac{a+\sqrt{a^2-9}}{3}\)