ai giúp mik với mai phải nộp rồi

\(\dfrac{12}{13}\)= \(\dfrac{12.101}{13.101}\)= \(\dfrac{1212}{1313}\) (1)

\(\dfrac{12}{13}\) = \(\dfrac{12.\left(-10101\right)}{13.\left(-10101\right)}\) = \(\dfrac{-121212}{-131313}\)(2)

Từ (1) và (2) => \(\dfrac{12}{13}=\dfrac{1212}{1313}=\dfrac{-121212}{-131313}\)

Ta có: \(\frac{1212}{1313}=\frac{12x101}{13x101}=\frac{12}{13}\)

Vậy \(\frac{12}{13}=\frac{1212}{1313}\)

Ta có: 1212/1313 = 12.101/13.101= 12/13

Vì 12/13 = 12/13 nên 12/13 = 1212/1313

Vây...

hai PS đó = nhau .

k cho mình nha

\(\frac{121212}{141414}\times\frac{1313}{1212}\times\frac{2424}{2424}\)

\(=\frac{6}{7}\times\frac{13}{12}\times1\)

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

~ Hok tốt ~

kết quả là ; 1313/141414

sau nhắc mik

=12. 10101/ 14.10101 .   13.101/12.101.   1

rút gọn ta được: 13/14

hok tốt

kt

Bài 1 :

36/1212 = 3/101

13/1313 = 1/101

3/101 + 1/101 = 4/101

Vậy 36/1212 + 13/1313 = 4/101.

Bài 2 :

A = 5/13 + 1/2 + -5/9 + -3/6 + 4/-9

A = 5/13 + 1/2 + -5/9 + -1/2 + -4/9

A = (1/2 + -1/2) + (-5/9 + -4/9) + 5/13

A = 0 + (-1) + 5/13

A = (-1) + 5/13 = -13/13 + 5/13 = 8/13.

Chúc bạn học giỏi nhé.

1)4/101

2)-8/13

Bạn đợi chút nghe, tối nay mình làm cho

A =\(\frac{\frac{12}{13}+\frac{12}{131}-\frac{12}{1313}+\frac{12}{13131}}{\frac{15}{13}+\frac{15}{131}-\frac{15}{1313}+\frac{15}{13131}}=\frac{12.\left(\frac{1}{13}+\frac{1}{131}-\frac{1}{1313}+\frac{1}{13131}\right)}{15.\left(\frac{1}{13}+\frac{1}{131}-\frac{1}{1313}+\frac{1}{13131}\right)}=\frac{12}{15}=\frac{4}{5}\) 

Tick ủng hộ nha mọi người

a)\(A=\frac{17}{23}.\frac{8}{16}.\frac{23}{17}.\left(-80\right).\frac{3}{4}\)

    \(A=\left(\frac{17}{23}.\frac{23}{17}\right).\left(\frac{8}{16}.\frac{3}{4}\right).\left(-80\right)\)

     \(A=\frac{3}{8}.\left(-80\right)\)

     \(A=-30\)

b)\(C=\left(\frac{13}{23}+\frac{1313}{2323}-\frac{131313}{232323}\right).\left(\frac{1}{3}+\frac{1}{4}-\frac{7}{12}\right)\)

   \(C=\left(\frac{13}{23}+\frac{1313}{2323}-\frac{131313}{232323}\right).0\)

   \(C=0\)

a)Ta có:

\(\frac{1212}{1313}=\frac{12\cdot101}{13\cdot101}=\frac{12}{13}\)

Suy ra \(\frac{12}{13}=\frac{1212}{1313}\)

câu b lạ

a)
Ta có

\(\frac{12}{13}=\frac{12.101}{13.101}=\frac{1212}{1313}\)

\(\Rightarrow\frac{12}{13}=\frac{1212}{1313}\)

b)

Ta có

\(1-\frac{123}{124}=\frac{1}{124}\)

\(1-\frac{124}{125}=\frac{1}{125}\)

Mà  \(\frac{1}{124}>\frac{1}{125}\)

\(\Rightarrow1-\frac{123}{124}>1-\frac{124}{125}\)

\(\Rightarrow\frac{123}{124}< \frac{124}{125}\)

\(\Rightarrow\frac{123}{124}< \frac{124.1001}{125.1001}\)

\(\Rightarrow\frac{123}{124}< \frac{124124}{125125}\)

\(\frac{12}{13}và\frac{1212}{1212}\)

\(\frac{1212}{1313}=\frac{12.101}{13.101}\) \(\Rightarrow\) \(\frac{12}{13}\)

Mà \(\frac{12}{13}=\frac{12}{13}\) \(\Rightarrow\) \(\frac{12}{13}=\frac{1212}{1313}\)

\(\frac{123}{124}\) và \(\frac{124124}{125125}\)

\(1-\frac{123}{124}\) = \(\frac{1}{124}\)

\(1-\frac{124124}{125125}\) = \(\frac{1}{125}\)

Mà \(\frac{1}{124}>\frac{1}{125}\) 

\(\Rightarrow\) \(1-\frac{123}{124}\) > \(1-\frac{124}{125}\)

\(\Rightarrow\) \(\frac{123}{124}\) <\(\frac{124}{125}\) \(\Rightarrow\)  \(\frac{123}{124}\) < \(\frac{124.1001}{125.1001}\)

\(\Rightarrow\) \(\frac{123}{124}< \frac{124124}{125125}\)

                                Chẳng biết có đúng hay không 

                                         Chúc bạn học tốt

=>B=\(\frac{12.\left(\frac{1}{13}+\frac{1}{1313}+\frac{1}{131}+\frac{1}{1313}\right)}{15.\left(\frac{1}{13}+\frac{1}{1313}+\frac{1}{131}+\frac{1}{1313}\right)}\)

=>B=\(\frac{12}{15}\)

=>B=\(\frac{4}{5}\)

B = \(\frac{12.\left(\frac{1}{13}+\frac{1}{1313}+\frac{1}{131}-\frac{1}{1313}\right)}{15.\left(\frac{1}{13}+\frac{1}{131}-\frac{1}{1313}+\frac{1}{1313}\right)}\)

=\(\frac{12.\left(\frac{1}{13}+\frac{1}{131}\right)}{15.\left(\frac{1}{13}+\frac{1}{131}\right)}\)

=\(\frac{12}{15}=\frac{4}{5}\)

Vậy B = 4/5.

B=\(\frac{\frac{12}{13}+\frac{12}{1313}+\frac{12}{131}-\frac{13}{1313}}{\frac{15}{13}+\frac{15}{131}-\frac{15}{1313}+\frac{15}{1313}}\)

B=\(\frac{\frac{12}{13}+\frac{12}{131}}{\frac{15}{13}+\frac{15}{131}}\)

B=\(\frac{12\cdot\left(\frac{1}{13}+\frac{1}{131}\right)}{15\cdot\left(\frac{1}{13}+\frac{1}{131}\right)}\)

Chia cả tử và mẫu B cho \(\frac{1}{13}\)+\(\frac{1}{131}\)(rút gọn phân số)

Ta được:B=\(\frac{12}{15}\)=\(\frac{4}{5}\)