JEE Main2017MathematicsCircleActual
If a point P 0 , - 2 and Q is any point on the circle, x 2 + y 2 - 5 x - y + 5 = 0 , then the maximum value of P Q 2 is
Options
- A8 + 5 3
- B47 + 10 6 2
- C14 + 5 3
- D25 + 6 2
Correct answer
C. 14 + 5 3
Step-by-step solution
Given circle x 2 + y 2 - 5 x - y + 5 = 0 ⇒ x - 5 2 2 + y - 1 2 2 = 3 2 On circle Q = ( 5 2 + 3 2 cos θ , 1 2 + 3 2 sin θ ) P Q 2 = 5 2 + 3 2 cos ⁡ θ​ 2 + 5 2 + 3 2 sin ⁡ θ​ 2 P Q 2 = 25 2 + 3 2 + 5 3 2 cos θ​ + sin θ​ = 14 + 5 3 2 cos ⁡ θ​ + sin ⁡ θ​ ∴ Maximum value of P Q 2 = 14 + 5 3 2 2 = 14 + 5 3 .