Ta có : 999/556 = 999 : 556

                        = 1,7967625....

1000/577 = 1000 : 577

               = 1,7331022....

Ta thấy : 1,7967625... > 1,7331022

Vậy : 999/556 > 1000/577

Ta có : \(\frac{999}{556}=1+\frac{443}{556}\)

           \(\frac{1000}{577}=1+\frac{423}{577}\)

Ta thấy : \(\frac{443\cdot577}{556\cdot577}=\frac{443}{556}\)

             \(\frac{423\cdot556}{577\cdot556}=\frac{423}{577}\)

Ta có : \(443\cdot577=443\cdot\left(556+21\right)=443\cdot556+443\cdot21\)

Ta thấy : \(423\cdot556\)< \(443.556+21\cdot556\)

=>\(\frac{423\cdot556}{577\cdot556}< \frac{443\cdot577}{556\cdot577}\)

=>\(\frac{1000}{577}< \frac{999}{556}\)

Vậy \(\frac{999}{556}>\frac{1000}{557}\)

\(A=2^0+2^1+2^2+...+2^{20}\)

\(2A=2^1+2^2+2^3+...+2^{21}\)

\(A=2^{21}-1\)

Vậy \(A>B\)

1 - \(\frac{999}{556}\) = \(\frac{-443}{556}\)

1 - \(\frac{1000}{557}\) = \(\frac{-443}{557}\)

Vì \(\frac{-443}{556}\) < \(\frac{-443}{557}\) nên \(\frac{999}{556}\) > \(\frac{1000}{557}\)

First we have :

\(\frac{999}{556}=\frac{999\cdot557}{556\cdot557}\)

Then : \(999\cdot557=999\cdot556+999\)

Next we have : \(1000\cdot556=999\cdot556+556\)

As you see : \(999\cdot556+556< 999\cdot556+999\)

So :\(\frac{999}{556}< \frac{1000}{557}\)

a ) Ta có 

\(\frac{29}{33}>\frac{29}{37}\)( đồng tử khác mẫu )

\(\frac{22}{37}< \frac{29}{37}\)( đồng mẫu khác tử )

=> \(\frac{29}{33}>\frac{29}{37}>\frac{22}{37}\)

b )  \(\frac{163}{257}< \frac{163}{221}\)

  \(\frac{162}{257}>\frac{149}{257}\)

  \(\Rightarrow\frac{163}{221}>\frac{163}{257}>\frac{149}{257}\)

a) ta có: \(\frac{22}{37}< \frac{29}{37}\)

\(\frac{29}{33}>\frac{29}{37}\)

\(\Rightarrow\frac{22}{37}< \frac{29}{37}< \frac{29}{33}\)

b) ta có: \(\frac{163}{257}>\frac{149}{257}\)

\(\frac{163}{221}>\frac{163}{257}\)

\(\Rightarrow\frac{163}{221}>\frac{163}{257}>\frac{149}{257}\)