12/13>22/33

tích mình mình tích lại cho 

Lưu ý : phải gửi tin nhắn

\(\frac{12}{13}>\frac{22}{33}\)

OK

12/13<22/33

ta có 6.5^22=6/5.5.5^22=6/5.5^23

vậy 6/5.5^23>5^23 hay 6.5^22>5^23

ta có 2^16=2^13.2^3=2^13.8

vì 8.7 nên 2^16 .> 2^13.7

a) 5^23 = 5^22 . 5

Mà 5 < 6 nên 5^23 < 6 . 5^22

b) 2^16 = 2^13 . 2^3 = 2^13 . 8

Mà 7 < 8 nên 7 . 2^13 < 2^16.

13^14 < hơn... dùm mình nha

ta có \(13^{13}>12^{13};13^{13}>11^{13};13^{13}>10^{13};...;13^{13}>2^{13};13^{13}>1^{13}\)

^{=>\(13^{13}\cdot12>12^{13}+11^{13}+10^{13}+...+2^{13}+1^{13}\)}

^{=>\(13^{13}\cdot13>12^{13}+11^{13}+10^{13}+...+2^{13}+1^{13}\)}

^{=>\(13^{14}>12^{13}+11^{13}+10^{13}+...+2^{13}+1^{13}\)}

\(\frac{13}{15}< \frac{11}{13}\)

\(\frac{8}{5}< \frac{7}{4}\)

\(\frac{8}{9}< \frac{4}{5}\)

\(\frac{7}{15}< \frac{21}{4}\)

Theo thứ tự≥≥≥= k mik nhé!

cái này thì mình ko bít nhưng mình nghĩ chắc bn thích gangaa đúng ko?

\(11^{12}< 11^{13}\)

\(7^4< 8^4\)

\(\left(6-5\right)^{432}=\left(7-6\right)^{943}\)

11¹² nhỏ hơn 

8⁴ lớn hơn

= nhau 

11^2 <11^3

7^4 < 8^4

(6-5)^432 = (7 - 6)^943 (kq đều = 1)

Ta có:

\(\frac{1}{11}+\frac{1}{12}+\frac{1}{13}+\frac{1}{14}+...+\frac{1}{25}\)

\(=\left(\frac{1}{11}+\frac{1}{12}\right)+\left(\frac{1}{13}+\frac{1}{14}+\frac{1}{15}\right)+\left(\frac{1}{16}+...+\frac{1}{20}\right)+\left(\frac{1}{21}+...+\frac{1}{25}\right)\)

Mà:

\(\frac{1}{11}+\frac{1}{12}>\frac{1}{12}+\frac{1}{12}=\frac{2}{12}=\frac{10}{60}\)

\(\frac{1}{13}+\frac{1}{14}+\frac{1}{15}>\frac{1}{15}+\frac{1}{15}+\frac{1}{15}=\frac{3}{15}=\frac{12}{60}\)

\(\frac{1}{16}+\frac{1}{17}+\frac{1}{18}+\frac{1}{19}+\frac{1}{20}>\frac{1}{20}+\frac{1}{20}+\frac{1}{20}+\frac{1}{20}+\frac{1}{20}=\frac{5}{20}=\frac{15}{60}\)

\(\frac{1}{21}+\frac{1}{22}+\frac{1}{23}+\frac{1}{24}+\frac{1}{25}>\frac{1}{25}+\frac{1}{25}+\frac{1}{25}+\frac{1}{25}+\frac{1}{25}=\frac{5}{25}=\frac{12}{60}\)

\(\Rightarrow\left(\frac{1}{11}+\frac{1}{12}\right)+\left(\frac{1}{13}+\frac{1}{14}+\frac{1}{15}\right)+\left(\frac{1}{16}+...+\frac{1}{20}\right)+\left(\frac{1}{21}+...+\frac{1}{25}\right)>\frac{10}{60}+\frac{12}{60}+\frac{15}{60}+\frac{12}{60}=\frac{49}{60}\)\(\Rightarrow\frac{1}{11}+\frac{1}{12}+\frac{1}{13}+\frac{1}{14}+...+\frac{1}{25}>\frac{49}{60}\left(đpcm\right)\)

vote mik tại đây nhé.Mik làm giúp bạn Gia Bảo bạn có thể qua xem ,xem xong rồi nhớ k mik ở đây nhé.

2.B=1+5+5^2+...+5^98

B=1+5^2+5^3+...+5^96+5^97+5^98

B=(1+5+5^2)+(5^3+5^4+5^5)+...+(5^96+5^97+5^98)
B=(1+5+25)+5^3.(1+5+25)+...+5^96.(1+5+25)

B=31+5^3.31`+...+5^96.31

B=(1+5^3+...+5^98).31.Suy ra B chia hết cho 31.