Question

Chứng minh rằng:

\(\frac{3}{10}+\frac{3}{11}+\frac{3}{12}+\frac{3}{13}+\frac{3}{14}>1\)

Giải cụ thể giùm mình nha. Thanks trước

Answer 1

\(\frac{3}{10}+\frac{3}{11}+\frac{3}{12}+\frac{3}{13}+\frac{3}{14}>\frac{3}{14}+\frac{3}{14}+\frac{3}{14}+\frac{3}{14}+\frac{3}{14}\)

(Vì \(\frac{3}{10}>\frac{3}{14};\frac{3}{11}>\frac{3}{14};\frac{3}{12}>\frac{3}{14};\frac{3}{13}>\frac{3}{14}\))

=> \(\frac{3}{10}+\frac{3}{11}+\frac{3}{12}+\frac{3}{13}+\frac{3}{14}>5.\frac{3}{14}=\frac{15}{14}>1\)

=> \(\frac{3}{10}+\frac{3}{11}+\frac{3}{12}+\frac{3}{13}+\frac{3}{14}>1\)