If `theta`
is the angle between the two radii (one to each circle) drawn from one
of the point of intersection of two circles `x^2+y^2=a^2`
and `(x-c)^2+y^2=b^2,`
then prove that the length of the common chord of the two circles is `(2a bsintheta)/(sqrt(a^2+b^2-2a bcostheta))`
A. `(ab)/(sqrt(a^(2)+b^(2)-2ab cos theta))`
B. `(2ab)/(sqrt(a^(2)+b^(2)-2ab cos theta))`
C. `(2ab sin theta)/(sqrt(a^(2)+b^(2)-2ab cos theta))`
D. `(2ab cos theta)/(sqrt(a^(2)+b^(2)-2ab cos theta))`
