In the following figure, arc AB is a quadrant of the circle with centre at point O and radius 4 units. Further, OC = OD, OC:OA = 3:4. A circle C is drawn such that it touches the quadrant at the point Y and the mid-point of AB at X. What is the radius(in units) of the circle C?
Now, AO=4 & AOX=45∘
⇒ AX = XO = 2√2
Thus, XY= 4 - 2√2 and the radius of the circle = 4−2√22 = 2 - √2