j: \(=\dfrac{4\sqrt{5}-\left(5+\sqrt{5}\right)\left(1+\sqrt{5}\right)}{4\sqrt{5}\left(\sqrt{5}+1\right)}\)
\(=\dfrac{4\sqrt{5}-5-5\sqrt{5}-\sqrt{5}-5}{4\sqrt{5}\left(\sqrt{5}+1\right)}=\dfrac{-2\sqrt{5}-10}{4\sqrt{5}\left(\sqrt{5}+1\right)}\)
\(=\dfrac{-1}{2}\)
i: \(L=\dfrac{3+2\sqrt{2}}{1}+\dfrac{\sqrt{2}-1}{1}\)
=3+2căn 2+căn 2-1
=3căn 2+2
n: \(=\dfrac{-6\left(\sqrt{3}+1\right)}{2}-\dfrac{2\sqrt{3}\left(2-\sqrt{3}\right)}{1}\)
=-3(căn 3+1)-4căn 3+6
=-3căn 3-3-4căn 3+6
=-7căn 3+3
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