\(\dfrac{196}{197+198}< \dfrac{196}{197};\dfrac{197}{197+198}< \dfrac{197}{198}\)

=>B<A

\(B=\frac{196+197}{197+198}=\frac{196}{197+198}+\frac{197}{197+198}\)

\(\frac{196}{197}>\frac{196}{197+198};\frac{197}{198}>\frac{197}{197+198}\)

=>A>B

\(A=\frac{196}{197}+\frac{197}{198}=\left(1-\frac{1}{197}\right)+\left(1-\frac{1}{198}\right)=1-\frac{1}{197}+1-\frac{1}{198}=1-\frac{1}{197}+\frac{197}{197}-\frac{1}{198}\)\(=1-\frac{198}{197}-\frac{1}{198}=\frac{197}{197}-\frac{198}{197}-\frac{1}{198}=\frac{-1}{197}-\frac{1}{198}

Tui cx k bt

\(=1-\frac{198}{197}-\frac{1}{198}=\frac{197}{197}-\frac{198}{197}-\frac{1}{198}=\frac{-1}{197}-\frac{1}{198}

A>B chắc luôn likeeeeeeeeeeeeeeeeeee đi

takefusa kubo

Vi 196/197 =196/197

=>ta so sanh 197/198 va 198

198=39204/198

197/198 < 39204/198 (vi 197 < 39204 )

=>A < B 

Vay A < B 

MÌH LÀ NG THANKS BẠN MỚI ĐÚG THANKS

không hiểu lắm

B=\(\frac{196+197}{197+198}\)= \(\frac{196}{197+198}\)+ \(\frac{197}{197+198}\)

ta có \(\frac{196}{197+198}\)< \(\frac{196}{197}\)

\(\frac{197}{197+198}\)< \(\frac{197}{198}\)

=> \(\frac{196}{197+198}\)+ \(\frac{197}{197+198}\)< \(\frac{196}{197}\)+ \(\frac{197}{198}\)

=> B < A

196/197 + 197/198 > 198/199 + 199/197

A=b ngu nhu cho

A bằng b nha bạn 

A=B , K CHO MINK NHÉ