JEE Main2014MathematicsCircleActual
If the point 1 , 4 lies inside the circle x 2 + y 2 - 6 x + 10 y + p = 0 and the circle does not touch or intersect the coordinate axes, then the set of all possible values of p is the interval
Options
- A25 ,   39
- B25 ,   29
- C0 ,   25
- D9 ,   25
Correct answer
B. 25 ,   29
Step-by-step solution
x 2 + y 2 - 6 x - 1 0 y + p = 0 ∴ Centre is 3 ,   5 and radius is 34 - p . ∵   1 ,   4 lies inside the circle. So, 1 + 16 - 6 - 40 + p < 0 ⇒ p < 29             . . . 1 Circle neither touches nor cut the coordinate axes. So, radius of circle 34 - p < 5 (for not touching x - axis ) and 34 - p < 3 (for not touching y - axis) ⇒   9 < p and 25 < p   ⇒   p > 25       . . . 2 From equations