\(\left(19^{21}+19^{22}+19^{23}\right):\left(19^{20}+19^{21}+19^{22}\right)\)

\(=19^{21}.\left(1+19+19^2\right):19^{20}:\left(1+19+19^2\right)=19\)

19 mũ 2

Có \(\frac{18}{18+19+20}>\frac{18}{18+19+20+21}\)

\(\frac{19}{18+19+21}>\frac{19}{18+19+20+21}\)

\(\frac{20}{18+19+21}>\frac{20}{18+19+20+21}\)

\(\frac{21}{18+19+21}>\frac{21}{18+19+20+21}\)

=> \(\frac{18}{18+19+20}+\frac{19}{18+19+21}+\frac{20}{18+19+21}+\frac{21}{18+19+21}>\frac{18}{18+19+20+21}+\frac{19}{18+19+20+21}+\frac{20}{18+19+20+21}+\frac{21}{18+19+20+21}\)

=> \(\frac{18}{18+19+20}+\frac{19}{18+19+21}+\frac{20}{18+19+21}+\frac{21}{18+19+21}>\frac{18+19+20+21}{18+19+20+21}\)

=>\(\frac{18}{18+19+20}+\frac{19}{18+19+21}+\frac{20}{18+19+21}+\frac{21}{18+19+21}>1\)

=>M>1

Còn lại mình không biết, đúng thì tick nha

bạn viết rõ lũy thừa giúp mình với

\(A=B\)

C = D

olm duyệt đi

ca cach giai

( 1 + 23 ) x 23 : 2 = 276 

rất dễ đấy☺☺

bn ơi , bn có thể ghi rõ đề bài đc ko??

ghi làm sao vậy bạn

Đặt \(A=\frac{10^{19}+1}{10^{20}+1};B=\frac{10^{21}+1}{10^{22}+1}\)

Ta có: \(10A=\frac{10^{20}+10}{10^{20}+1}=\frac{10^{20}+1+9}{10^{20}+1}=1+\frac{9}{10^{20}+1}\)

\(10B=\frac{10^{22}+10}{10^{22}+1}=\frac{10^{22}+1+9}{10^{22}+1}=1+\frac{9}{10^{22}+1}\)

Ta có: \(10^{20}+1<10^{22}+1\)

=>\(\frac{9}{10^{20}+1}>\frac{9}{10^{22}+1}\)

=>\(\frac{9}{10^{20}+1}+1>\frac{9}{10^{22}+1}+1\)

=>10A>10B

=>A>B