Răspuns :
fie √2 = numar irational
dem 2 < √2 <3 ridicam la patrat 2² < 2 < 3² fals
↓
4 < 2 fals , √2 ∈ ( 2,3)
dem 2 < √6 <3 ridicam la patrat 2² < 6 < 3² ⇒ 4< 6 <9 adevarat
√6 ∈ ( 2 ,3)
dem 2 < √2 <3 ridicam la patrat 2² < 2 < 3² fals
↓
4 < 2 fals , √2 ∈ ( 2,3)
dem 2 < √6 <3 ridicam la patrat 2² < 6 < 3² ⇒ 4< 6 <9 adevarat
√6 ∈ ( 2 ,3)