Question

Chứng minh :  \(\overline{abab}+\overline{ab}⋮3\)

Answer 1

Ta có :

 \(\overline{abab}+\overline{ab}\)

= \(\overline{ab}.101+\overline{ab}.1\)

= \(\overline{ab}.\left(101+1\right)\)

= \(\overline{ab}.\left(102\right)\)

Mà 102 chia hết cho 3 → \(\overline{ab}.\left(102\right)\)\(⋮3\)