find the value of under root 5 ? briefly.?
For this, we draw a number line and mark the integers −2, −1, 0, 1, 2, 3, 4, etc. on it, so that the distance between any two consecutive integers is one unit. On this number line, we mark O and A at the points 0 and 2 respectively. At A, we draw AB of unit length which is perpendicular to OA. Now, we join OB. Taking O as the centre and OB as the radius, we will draw an arc which cuts the number line at P.
Now, point P represents the irrational numberon the number line. Let us verify it.
Using Pythagoras theorem in ΔOAB,
OB2 = OA2 + AB2
= 22 + 12
= 4 + 1
But OP = OB