Q. Angle between tangent drawn to circle $x^{2} + y^{2} = 20$, from the point (6, 2) is
A) $\frac{\pi}{2}$
B) $\pi$
C) $\frac{\pi}{4}$
D) $2\pi$
Explanation
(a)
Let $S = x^{2} + y^{2} - 20$
At point $(6,\ 2)$; $S_{1} = 6^{2} + 2^{2} - 20 = 20$
$\therefore\ \ \theta = 2\tan^{- 1}\frac{r}{\sqrt{S_{1}}} = 2\tan^{- 1}\frac{\sqrt{20}}{\sqrt{20}} = \frac{\pi}{2}$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.