Mathematics

Problem

If two parallel chords of a circle, having diameter 4 units, lie on the opposite sides of the centre and subtend angles

\cos^{-1}\left(\frac{1}{7}\right)

and

\sec^{-1}(7)

at the centre respectively, then the distance between these chords, is : (1)

\frac{16}{7}

(2)

\frac{8}{7}

(3)

\frac{4}{\sqrt{7}}

(4)

\frac{8}{\sqrt{7}}