$\\$
`-> A`
giải thích :
$A=\dfrac{\dfrac{2}{3}-\dfrac{2}{5}+\dfrac{2}{10} }{\dfrac{8}{3}-\dfrac{8}{5}+\dfrac{8}{10} } + \dfrac{1}{2}$
$→ A=\dfrac{2 (\dfrac{1}{3}-\dfrac{1}{5}+\dfrac{1}{10})}{8(\dfrac{1}{3}-\dfrac{1}{5}+\dfrac{1}{10} )} + \dfrac{1}{2}$
$→ A=\dfrac{2.1}{8.1} + \dfrac{1}{2}$
$→ A=\dfrac{1}{4}+\dfrac{2}{4}$
$→A=\dfrac{3}{4}$
$→ A=0,75$
Ta thấy : $0,75 < 1$
$→ A < 1$
