GATE | GATE CS 2018 | Question 5
The area of a square is ‘d’. What is the area of the circle which has the diagonal of the square as its diameter?
(C) (1/4) πd2
One important observation to solve the question : Diagonal of Square = Diameter of Circle. Let side of square be x. From Pythogorous theorem. Diagonal = √(2*x*x) We know area of square = x * x = d Diameter = Diagonal = √(2*d) Radius = √(d/2) Area of Circle = π * √(d/2) * √(d/2) = 1/2 * π * d