Ta có: 21/11 + 19/36 + 11/36 = 21/11 + ( 19/36 + 11/36 ) = 21/11 + 30/36 = 21/11 + 5/6 = 126/66 + 55/66 = 181/66 = \(2\frac{49}{66}\)
Mà \(2\frac{49}{66}< 3\Rightarrow\frac{21}{11}+\frac{19}{36}+\frac{11}{36}< 3\)
Chắc vậy! k cho mình nha!
Ta có: \(\frac{21}{11}-1+\frac{19}{36}-1+\frac{11}{36}-1=\frac{10}{11}-\frac{7}{6}=-\frac{17}{66}< 0.\)
\(\Rightarrow\frac{21}{11}+\frac{19}{36}+\frac{11}{36}< 3lđ.\)
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