Shukant Pal
Last Activity: 7 Years ago
In this question, you just need to apply the condition of tangency of a line w.r.t to a circle, .i.e, perpendicular distance of the line from the center of the circle is equal to its radius.
The equation of the line is – hx + ky – 1/a = 0 and C(0, 0) and radius of circle is ‘a’.
Thus, |[0*h + 0*k – 1/a] / sqrt(h2 + k2)]| = a.
Solving this you will get – sqrt(h2 + k2) = 1/a2 or radius of circle is 4) 1/a2
