Question

1/3+1/4+1/5+1/6+1/7+1/8<2
DAU COROANA
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Answer 1

Explicație pas cu pas:

$\frac{1}{3} \leqslant \frac{1}{3} \\ \frac{1}{4} < \frac{1}{3} \\ \frac{1}{5} < \frac{1}{3} \\ \frac{1}{6} < \frac{1}{3} \\ \frac{1}{7} < \frac{1}{3} \\ \frac{1}{8} < \frac{1}{3}$

$\frac{1}{3} + \frac{1}{4} + \frac{1}{5} + \frac{1}{6} + \frac{1}{7} + \frac{1}{8} < \frac{1}{3} + \frac{1}{3} + \frac{1}{3} + \frac{1}{3} + \frac{1}{3} + \frac{1}{3} \\ \frac{1}{3} + \frac{1}{4} + \frac{1}{5} + \frac{1}{6} + \frac{1}{7} + \frac{1}{8} < 6 \cdot \frac{1}{3} \\ \implies \frac{1}{3} + \frac{1}{4} + \frac{1}{5} + \frac{1}{6} + \frac{1}{7} + \frac{1}{8} < 2$