1+1=?
2+2=?
12+12=?
1212+1212=?
121212+121212=?
12121212+12121212=?
574546454156435545465+6465486646476464846=?
\(\frac{121212+12121212-1212}{363636+36363636-3636}\)
tính nhanh
\(\frac{121212+12121212-1212}{363636-36363636-3636}=\frac{12\left(111111+11111111-1111\right)}{36\left(111111+11111111-1111\right)}=\frac{12}{36}=\frac{1}{3}\)
\(\frac{1}{3}\)
chúc ban hk tốt!!(k cho tui nhé)
\(\frac{121212+12121212-1212}{363636+36363636-3636}\)
Nhờ các bạn tính nhanh hộ mình
\(\frac{121212+12121212-1212}{363636+36363636-3636}\)
\(=\frac{12.10101+12.1010101-12.101}{36.10101+36.1010101-36.101}\)
\(=\frac{12\left(10101+1010101-101\right)}{36\left(10101+1010101-101\right)}\)
\(=\frac{12}{12.3}\)
\(=\frac{1}{3}\)
Ta có: \(\frac{121212+12121212-1212}{363636+36363636-3636}\)
=\(\frac{12\times\left(10101+1010101-101\right)}{36\times\left(10101+1010101-101\right)}\)
=\(\frac{12}{36}\)
=\(\frac{1}{3}\)
\(\frac{121212+12121212-1212}{363636+36363636-3636}\)
\(=\frac{121212+12121212-1212}{3\times121212+3\times12121212-3\times1212}\)
\(=\frac{121212+12121212-1212}{3\times\left(121212+12121212-1212\right)}\)
\(=\frac{1}{3}\)
_Chúc bạn học tốt_
Tính nhanh :
a) \(\frac{2015\cdot2017-1}{2014+2015\cdot2016}\)
b) \(\frac{1}{1\cdot5}+\frac{1}{5\cdot9}+...+\frac{1}{2011\cdot2015}\)
c)\(\frac{12}{35}+\frac{1212}{3535}+\frac{121212}{353535}+\frac{12121212}{35353535}\)
a,\(\frac{2015.2016+2015-1}{2014+2015.2016}=\frac{2015.2016+2014}{2014+2015.2016}=1\)\(1\)
b,\(=1-\frac{1}{5}+\frac{1}{5}...-\frac{1}{2011}+\frac{1}{2011}-\frac{1}{2015}=1-\frac{1}{2015}=\frac{2014}{2015}\)
c,\(=\frac{12}{35}+\frac{12}{35}+\frac{12}{35}+\frac{12}{35}=\frac{12}{35}.4=\frac{48}{35}\)
b>=1-1/5+1/5-1/9+...+1/2011-1/2015
=1-1/2015
=2014/2015
c>=12/35+12/35+12/35+12/35
=12/35x4
=48/35
Chứng minh các phân số sau bằng nhau.
12/13 = 1212/1313 = -121212/-131313
\(\dfrac{12}{13}\)= \(\dfrac{12.101}{13.101}\)= \(\dfrac{1212}{1313}\) (1)
\(\dfrac{12}{13}\) = \(\dfrac{12.\left(-10101\right)}{13.\left(-10101\right)}\) = \(\dfrac{-121212}{-131313}\)(2)
Từ (1) và (2) => \(\dfrac{12}{13}=\dfrac{1212}{1313}=\dfrac{-121212}{-131313}\)
121212 phần 212121 và 12121212 phần 21212121
so sánh phân số
Giusp mình nhé . Mình cảm ơn ạ !
\(\dfrac{121212}{212121}\) < \(\dfrac{12121212}{21212121}\)
\(\dfrac{121212}{212121}< \dfrac{12121212}{21212121}\)
Tính
\(A=\frac{12}{13}+\frac{1212}{1313}+\frac{121212}{131313}+...+\frac{\underrightarrow{1212...12}2012số12}{\underrightarrow{1313...13}2012so13}\)
\(C=\frac{5}{2\times0,237237...}+\frac{5}{2\times0,0237237...}+\frac{5}{2\times0,00237237}\)
\(D=\) số các ước dương của 2492820
so sánh hai phân số sau:
a) 121212 trên 212121 và 12121212 trên 21212121
b) 2+1 trên -50 và -82 trên 4
a: \(\dfrac{121212}{212121}=\dfrac{4}{7}\)
\(\dfrac{12121212}{21212121}=\dfrac{4}{7}\)
Do đó: \(\dfrac{121212}{212121}=\dfrac{12121212}{21212121}\)
b: \(2+\dfrac{1}{-50}=\dfrac{99}{50}=1.98>0>-\dfrac{82}{4}\)
Rút gọn các phân số sau :
a )1212 / 1313
b) 121212/131313
c) 121121/ 131131
a:\(\dfrac{12}{13}\)
b:\(\dfrac{12}{13}\)
c:\(\dfrac{121}{131}\)
Câu a: \(\dfrac{12}{13}\)
Câu b: \(\dfrac{12}{13}\)
Câu c: \(\dfrac{121}{121}\)
A= 121212/363636+1212/3636
mn giúp mk nha
\(A=\frac{121212}{363636}+\frac{1212}{3636}\)
\(=\frac{1}{3}+\frac{1}{3}=\frac{2}{3}\)
#)Giải :
\(\frac{121212}{363636}=\frac{121212:10101}{363636:10101}=\frac{12}{36}=\frac{1}{3}\)
\(\frac{1212}{3636}=\frac{1212:101}{3636:101}=\frac{12}{36}=\frac{1}{3}\)
\(\Rightarrow A=\frac{1}{3}+\frac{1}{3}=\frac{2}{3}\)