Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.
![](https://rs.olm.vn/images/avt/0.png?1311)
Cần nhớ:
\(\frac{a}{b}< 1\Rightarrow\frac{a}{b}< \frac{a+n}{b+n}\left(n\inℕ^∗\right)\)
\(\frac{a}{b}>1\Rightarrow\frac{a}{b}>\frac{a+n}{b+n}\left(n\inℕ^∗\right)\)
Ta thấy:
\(\frac{19}{29}< 1\Rightarrow\frac{19}{29}< \frac{19+1}{29+1}=\frac{20}{30}=\frac{2}{3}\)
Ta lại có:
\(\frac{2}{3}=\frac{2.7}{3.7}=\frac{14}{21}< 1\Rightarrow\frac{14}{21}< \frac{14+6}{21+6}=\frac{20}{27}=\frac{20.3}{27.3}=\frac{60}{81}\)
\(\Rightarrow\frac{19}{29}< \frac{60}{81}\) (1)
Ta có:
\(\frac{60}{81}=\frac{20}{27}< 1\Rightarrow\frac{20}{27}< \frac{20+1}{27+1}=\frac{21}{28}< \frac{21}{25}\)
=>\(\frac{60}{81}< \frac{21}{25}\) (2)
Từ (1) và (2) => \(\frac{19}{29}< \frac{60}{81}< \frac{21}{25}\)
![](https://rs.olm.vn/images/avt/0.png?1311)
\(\frac{21}{25}=\frac{49329}{58725}\)
\(\frac{60}{81}=\frac{43500}{58725}\)
\(\frac{19}{29}=\frac{38475}{58725}\)
\(\)vì \(\frac{49329}{58725}>\frac{43500}{58725}>\frac{38475}{58725}\)nên\(\frac{21}{25}>\frac{60}{81}>\frac{19}{29}\)
\(\frac{21}{25};\frac{60}{81};\frac{19}{29}\)
Ta có : \(\frac{60}{81}=\frac{60:3}{81:3}=\frac{20}{27}\); giữ nguyên \(\frac{21}{25};\frac{19}{29}\).
Vì \(\frac{21}{25}>\frac{20}{25}>\frac{20}{27}\)nên \(\frac{21}{25}>\frac{20}{27}\)
Vì \(\frac{20}{27}>\frac{20}{29}>\frac{19}{29}\)nên \(\frac{20}{27}>\frac{19}{29}\). Vậy :
\(\frac{21}{25}>\frac{20}{27}>\frac{19}{29}\)hay \(\frac{21}{25}>\frac{60}{81}>\frac{19}{29}\)
![](https://rs.olm.vn/images/avt/0.png?1311)
12/18<13/17
vì 12<13 nên 12/18<1/17
13/41<25/77
vì 13<25 nên 13/41<25/77
![](https://rs.olm.vn/images/avt/0.png?1311)
\(\frac{21}{25};\frac{60}{81};\frac{19}{29}\)
Đúng 100% Chúc bạn zui ~^^
![](https://rs.olm.vn/images/avt/0.png?1311)
ta có: \(1-\frac{17}{20}=\frac{3}{20};1-\frac{22}{25}=\frac{3}{25}\)
\(\Rightarrow\frac{3}{20}>\frac{3}{25}\Rightarrow1-\frac{17}{20}>1-\frac{22}{25}\)
\(\Rightarrow\frac{17}{20}< \frac{22}{25}\)
![](https://rs.olm.vn/images/avt/0.png?1311)
Ta có :
\(1-\frac{13}{27}=\frac{14}{27}\)
\(1-\frac{27}{41}=\frac{14}{41}\)
Mà \(\frac{14}{27}>\frac{14}{41}\)
\(\Rightarrow1-\frac{13}{27}>1-\frac{27}{41}\)
\(\Rightarrow\frac{13}{27}< \frac{27}{41}\)
Chúc bạn học tốt !!!