Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.
\(\frac{52}{75}=\frac{52.101}{75.101}=\frac{5252}{7575};\frac{52}{75}=\frac{52.10101}{75.10101}=\frac{525252}{757575}\)
\(\frac{13}{15}=\frac{13.101}{15.101}=\frac{1313}{1515};\frac{13}{15}=\frac{13.10101}{15.10101}=\frac{131313}{151515}\)
\(\frac{ab}{cd}=\frac{101ab}{101cd}=\frac{abab}{cdcd};\frac{ab}{cd}=\frac{10101ab}{10101cd}=\frac{ababab}{cdcdcd}\)
ai k minh minh k lai
; 
; 
(điều này dễ chứng minh được)
;
= 2
;
<1
a)Ta có : \(\dfrac{1212}{1414}=\dfrac{12.101}{14.101}=\dfrac{12}{14}\)
\(\dfrac{121212}{242424}=\dfrac{12.10101}{24.10101}=\dfrac{12}{24}\)
Vậy \(\dfrac{12}{24}=\dfrac{1212}{2424}=\dfrac{121212}{242424}\)
Ta có : \(\dfrac{2424}{3535}=\dfrac{24.101}{35.101}=\dfrac{24}{35}\)
\(\dfrac{242424}{353535}=\dfrac{24.10101}{35.10101}=\dfrac{24}{35}\)
Vậy \(\dfrac{24}{35}=\dfrac{2424}{3535}=\dfrac{242424}{353535}\)
Ta có abab/cdcd=abab:101/cdcd:101=ab/cd
ababab/cdcdcd=ababab:10101/cdcdcd:10101=ab/cd
Vì ab/cd=ab/cd nên abab/cdcd= ababab/cdcdcd
\(\frac{abab}{cdcd}=\frac{ab.101}{cd.101}=\frac{ab}{cd}\)
\(\frac{ababab}{cdcdcd}=\frac{ab.10101}{cd.10101}=\frac{ab}{cd}\)
VẬY \(\frac{abab}{cdcd}=\frac{ababab}{cdcdcd}\)
1,
ta có : \(\frac{\overline{abab}}{\overline{cdcd}}=\frac{\overline{abab}:101}{\overline{cdcd}:101}=\frac{\overline{ab}}{\overline{cd}}\) ; \(\frac{\overline{ababab}}{\overline{cdcdcd}}=\frac{\overline{ababab}:10101}{\overline{cdcdcd}:10101}=\frac{\overline{ab}}{\overline{cd}}\)
Vậy \(\frac{\overline{abab}}{\overline{cdcd}}=\frac{\overline{ababab}}{\overline{cdcdcd}}\)
2,
\(\frac{1}{2}.\frac{1}{b}=\frac{2}{4}\)
\(\Rightarrow\frac{1.1}{2.b}=\frac{2}{4}\)
\(\Rightarrow\frac{1}{2.b}=\frac{1}{2}\)
\(\Rightarrow2.b=2\)
\(\Rightarrow b=2:2=1\)
\(\frac{abab}{cdcd}=\frac{abab:101}{cdcd:101}=\frac{ab}{cd}\)
mà \(\frac{ababab}{cdcdcd}=\frac{ababab:10101}{cdcdcd:10101}=\frac{ab}{cd}\)
=> \(\frac{abab}{cdcd}=\frac{ababab}{cdcdcd}\)
vậy...
câu 2
\(\frac{1}{2}.\frac{1}{b}=\frac{2}{4}\\ \Rightarrow\frac{1}{b}=\frac{2}{4}:\frac{1}{2}=1\\ \Rightarrow b=1\)
vậy....
1)
a) \(\frac{9^{14}.25^5.8^7}{18^{12}.625^3.24^3}=\frac{3^{28}.5^{10}.2^{21}}{2^{21}.3^{24}.5^{12}.3^3.2^9}=\frac{3}{5^2}=\frac{3}{25}\)
Bài 2:
\(\frac{abab}{cdcd}=\frac{ab.101}{cd.101}=\frac{ab}{cd};\frac{ababab}{cdcdcd}=\frac{ab.10101}{cd.10101}=\frac{ab}{cd}\)
Vậy \(\frac{ab}{cd}=\frac{abab}{cdcd}=\frac{ababab}{cdcdcd}\)
Hai phân số sau có bằng nhau không?
¯¯¯¯¯¯¯¯¯¯abab¯¯¯¯¯¯¯¯¯¯cdcd=¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯ababab¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯cdcdcd=\(\frac{ab}{cd}\)
\(\Rightarrow\) Hai phan so đều bằng nhau.
\(\frac{12}{14}=\frac{1212}{1414}=\frac{121212}{141414}\)
\(\frac{24}{35}=\frac{2424}{3535}=\frac{242424}{353535}\)
\(\frac{ab}{cd}=\frac{abab}{cdcd}=\frac{ababab}{cdcdcd}\)