what is

$$\\\frac{\sqrt{10}}{10}+\frac{1}{\sqrt{10}}\\\\
=\frac{\sqrt{10}}{10}+\frac{1*\sqrt{10}}{\sqrt{10}*\sqrt{10}}\\\\
=\frac{\sqrt{10}}{10}+\frac{\sqrt{10}}{10}\\\\
=\frac{2\sqrt{10}}{10}\\\\
=\frac{\sqrt{10}}{5}\\\\$$

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