c. \(\dfrac{\sqrt{10}-\sqrt{2}}{\sqrt{5}-1}+\dfrac{5}{\sqrt{7}-\sqrt{2}}-\dfrac{7}{\sqrt{7}}\)
\(=\dfrac{\left(\sqrt{10}-\sqrt{2}\right)\left(\sqrt{5}+1\right)}{4}+\dfrac{5\left(\sqrt{7}+\sqrt{2}\right)}{5}-\sqrt{7}\)
\(=\dfrac{\sqrt{50}-\sqrt{2}}{4}+\dfrac{\sqrt{175}+\sqrt{50}}{5}-\sqrt{7}\)
\(=\dfrac{4\sqrt{2}}{4}+\dfrac{5\left(\sqrt{7}+\sqrt{2}\right)}{5}-\sqrt{7}\)
\(=\sqrt{2}+\sqrt{7}+\sqrt{2}-\sqrt{7}\)
\(=2\sqrt{2}\)
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