2 câu trả lời
+ BCNN
` 27 = 3 . 7`
` 36 = 2² . 3²`
` 81 =` $3^{4}$
`=>` BCNN`(27;36;81)` `= 2² .` $3^{4}$ `. 7 = 2268`
+ ƯCLN
`27 = 3 . 7`
`36 = 2² . 3²`
`81 =` $3^{4}$
`=>` UWCLN`(27;36;81) = 3`
Ta có : `27=3^3`
`36=2^2 .3^2`
`81=3^4`
`=>BCNNN(27,36,81)=3^4 .2^2=324`
`ƯCLN(27,36,81)=3^2=9`