Question

Answer 1

a: Ta có: \(\sqrt{\dfrac{\sqrt{a}-1}{\sqrt{b}+1}}:\sqrt{\dfrac{\sqrt{b}-1}{\sqrt{a}+1}}\)

\(=\sqrt{\dfrac{a-1}{b-1}}\)

\(=\sqrt{\dfrac{6.25}{2.25}}=\dfrac{2.5}{1.5}=\dfrac{5}{3}\)

b: \(\sqrt{15a^2-8a\sqrt{15}+16}\)

\(=\left|a\sqrt{15}-4\right|\)

\(=\sqrt{8-4}=2\)