Construct BD of 1 unit length perpendicular to OB as fig. Join OD
By Pythagoras theorem, OD=√(√2)2+12=√2+1=√3
Using a compass, with centre O and radius OD, draw an arc which
intersects the number line at the point L right side to 0. Then
′L′ corresponds to √3. From this we can conclude that many
points on the number line can be represented by irrational numbers also.
In the same way, we can locate √n for any positive integers n, after √n−1 has been located.