\(a,\frac{-8}{15}=\frac{-8.12}{15.12}=\frac{-96}{180}\left(1\right)\)

\(\frac{7}{12}=\frac{7.15}{12.15}=\frac{105}{180}\left(2\right)\)

Từ 1 và 2 \(\Rightarrow\frac{-8}{15}< \frac{7}{12}\)

\(b,\frac{13}{19}=\frac{13.53}{19.53}=\frac{689}{1007}\left(1\right)\)

\(\frac{47}{53}=\frac{47.19}{53.19}=\frac{893}{1007}\left(2\right)\)

Từ 1 và 2 \(\Rightarrow\frac{13}{19}< \frac{47}{53}\)

\(\frac{14}{13}=1+\frac{1}{13}\)

\(\frac{15}{14}=1+\frac{1}{14}\)

Do   \(\frac{1}{13}>\frac{1}{14}\)

nên  \(\frac{14}{13}>\frac{15}{14}\)

\(\text{So sánh }2\text{ phân số : }\)

\(\frac{14}{13}\text{ và }\frac{15}{14}\)                             

\(\text{Ta có : }\)

\(\frac{14}{13}=1+\frac{1}{13}\)

\(\frac{15}{14}=1+\frac{15}{14}\)

\(\text{ Do : }\frac{1}{13}>\frac{1}{14}\)

\(\text{Nên : }\frac{14}{13}>\frac{15}{14}\)

14/13 >15/14

a)

\(\frac{13}{27}=\frac{13.101}{27.101}=\frac{1313}{2727}\)

=> \(\frac{13}{27}=\frac{1313}{2727}\)

b)

\(-\frac{15}{23}=-\frac{15.10101}{23.10101}=-\frac{151515}{232323}\)

=>\(-\frac{15}{23}=-\frac{151515}{232323}\)

a) \(\frac{1313}{2727}=\frac{1313:101}{2727:101}=\frac{13}{27}\)

Vậy \(\frac{13}{27}=\frac{1313}{2727}\)

b) \(-\frac{151515}{232323}=\frac{-151515:10101}{232323:10101}=-\frac{15}{23}\)

Vậy \(-\frac{15}{23}=-\frac{151515}{232323}\)

27^150=(3^3)^150=3^450 còn 9^=(3^3)^226=3^678. Vậy 9^226>27^150

Mai Anh tính sai rồi nha bạn dù kết quả của bạn vẫn đúng nha

27^150 = (3^3)^150 = 3^450

9^226= (3^2)^226 = 3^452 

Mà 3^452 > 3^450 suy ra  9^226 > 27^150

các bn nào đang online giải hộ mk vs

a)\(\frac{21}{11}.\frac{22}{17}.\frac{68}{63}=\frac{21.22.68}{11.17.63}=\frac{21.2.11.4.17}{11.17.3.21}=\frac{\left(11.17.21\right)2.4}{\left(11.17.21\right).3}=\frac{2.4}{3}=\frac{8}{3}\)

b)\(\frac{5}{14}.\frac{7}{13}.\frac{26}{25}=\frac{5.7.26}{14.13.25}=\frac{5.7.13.2}{7.2.13.5.5}=\frac{\left(5.7.13\right).2}{\left(5.7.13\right).2.5}=\frac{2}{2.5}=\frac{1}{5}\)

9²⁵ lớn hơn 4⁴⁰ hoặc 4⁴⁰ nhỏ hơn 9²⁵

>
 

A>B

mk nhắc rồi na

Anh qua câu hỏi của em đi, có ng trả lời mà, sao em hỏi nảy h anh ko trả lời

\(A=1+\frac{1}{2}+\frac{1}{3}+\frac{1}{4}+...+\frac{1}{15}+\frac{1}{16}\)

 \(=1+\left(\frac{1}{2}+\frac{1}{3}+\frac{1}{4}+\frac{1}{5}\right)+\left(\frac{1}{6}+\frac{1}{7}+\frac{1}{8}\right)+\left(\frac{1}{9}+\frac{1}{10}+\frac{1}{11}\right)+\left(\frac{1}{12}+\frac{1}{13}+\frac{1}{14}\right)\)

\(+\left(\frac{1}{15}+\frac{1}{16}\right)\)

Vì \(\frac{1}{6}+\frac{1}{7}+\frac{1}{8}< 3\times\frac{1}{6}=\frac{1}{2}\)

\(\frac{1}{9}+\frac{1}{10}+\frac{1}{11}< 3\times\frac{1}{9}=\frac{1}{3}\)

\(\frac{1}{12}+\frac{1}{13}+\frac{1}{14}< 3\times\frac{1}{12}=\frac{1}{4}\)

\(\frac{1}{15}+\frac{1}{16}< 3\times\frac{1}{15}=\frac{1}{5}\)

\(\frac{1}{2}+\frac{1}{3}+\frac{1}{4}+\frac{1}{5}< 3\times\frac{1}{2}=\frac{3}{2}\)

\(\Rightarrow A=1+\frac{1}{2}+\frac{1}{3}+\frac{1}{4}+...+\frac{1}{15}+\frac{1}{16}< 1+\frac{3}{2}+\frac{1}{2}+\frac{1}{3}+\frac{1}{4}+\frac{1}{5}\)

\(\frac{1}{6}+\frac{1}{7}+\frac{1}{8}+...+\frac{1}{15}+\frac{1}{16}< \frac{1}{2}+\frac{1}{3}+\frac{1}{4}+\frac{1}{5}\)

P.s Mình tịt rồi , bạn cố gắng giải ra nhá ^.^!!