Let be the circle with centre at and radius . If is the circle centred at passing through the origin and touching the circle externally, then the radius of is equal to
Explanation for correct option:
Finding the radius of :
Plotting the graph using the given information.
The distance formula is given by
We know
Equating Equation (1) and (2) we get
Squaring on both side
Therefore, option (D) is the correct answer.