Ta có:\(\frac{17}{21}+\frac{17}{20}+\frac{17}{19}>\frac{17}{21}+\frac{17}{21}+\frac{17}{21}\)
Mà :\(\frac{17}{21}+\frac{17}{21}+\frac{17}{21}=\frac{51}{21}>\frac{42}{21}=2\)
\(\Rightarrow\frac{17}{21}+\frac{17}{20}+\frac{17}{19}>2\left(đpcm\right)\)
Chúc Bạn Học Tốt (Tks PP)
chứng minh rằng:\(\frac{17^{18}+1}{17^{19}+1}< \frac{17^{18}+1+16}{17^{19}+1+16}\)
Tính A=\(\frac{\frac{1}{2}+\frac{1}{3}+\frac{1}{4}+...+\frac{1}{18}+\frac{1}{19}+\frac{1}{20}}{\frac{19}{1}+\frac{18}{2}+\frac{17}{3}+...+\frac{3}{17}+\frac{2}{18}+\frac{1}{19}}\)
\(\frac{\frac{1}{2}+\frac{1}{3}+\frac{1}{4}+...+\frac{1}{18}+\frac{1}{19}+\frac{1}{20}}{\frac{19}{1}+\frac{18}{2}+\frac{17}{3}+...+\frac{3}{17}+\frac{2}{18}+\frac{1}{19}}\)
Cho \(S=\frac{17}{18}+\frac{18}{19}+\frac{19}{20}+\frac{20}{17}\)
SO sánh S với 4
Tính \(A=\frac{\left(1+17\right)+\left(1+\frac{17}{2}\right)+\left(1+\frac{17}{3}\right).....\left(1+\frac{17}{19}\right)}{\left(1+19\right)\left(1+\frac{19}{2}\right)\left(1+\frac{19}{3}\right)....\left(1+\frac{19}{17}\right)}\)
Chứng minh:\(A=\frac{11}{29}+\frac{9}{17}+\frac{10}{19}\) <2
\(G = \frac{19}{17} . \frac{-4}{7} + \frac{19}{17} . \frac{-3}{7} + 1\frac{2}{17}\)
Bài này chứng minh sao các bạn?
A = \(\frac{11}{29}+\frac{9}{17}+\frac{10}{19}\). Chứng minh A < 2.
so sánh A=: \(\frac{17^{18}-1}{17^{20}-1}\)Và B= \(\frac{17^{17}-1}{17^{19}-1}\)
