Đáp án:
`M > N`
Giải thích các bước giải:
`M=7/2 sqrt(1/12)=sqrt((7/2)^2 . 1/12)=sqrt(49/4 . 1/12)`
`qquad =sqrt(49/48)`
`N=9/4 sqrt(1/5)=sqrt((9/4)^2 . 1/5)=sqrt(81/16 . 1/5)`
`qquad =sqrt(81/80)`
Ta có : `49/48=(48+1)/48=1+1/48 \ ; \81/80=(80+1)/80=1+1/80`
Vì : `1/48 > 1/80 to 1+1/48 > 1+1/80`
`to 49/48 > 81/80`
`to sqrt(49/48) > sqrt(81/80)`
`to 7/2 sqrt(1/2) > 9/4 sqrt(1/5)`
`to M > N`