Question

CMR

\(\frac{1}{\sqrt{1}}+\frac{1}{\sqrt{2}}+\frac{1}{\sqrt{3}}+...+\frac{1}{\sqrt{100}}>10\)

Answer 1

\(\frac{1}{\sqrt{1}}>\frac{1}{\sqrt{100}}=\frac{1}{10};\frac{1}{\sqrt{2}}>\frac{1}{\sqrt{100}}=\frac{1}{10};\frac{1}{\sqrt{3}}>\frac{1}{\sqrt{100}}=\frac{1}{10};...;\frac{1}{\sqrt{100}}=\frac{1}{10}\)

\(\text{Suy ra: }\frac{1}{\sqrt{1}}+\frac{1}{\sqrt{2}}+\frac{1}{\sqrt{3}}+...+\frac{1}{\sqrt{100}}>\frac{1}{10}+\frac{1}{10}+\frac{1}{10}+...+\frac{1}{10}=\frac{1}{10}.100=10\)

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