+305 
An equilateral triangle ABC is inscribed in the ellipse x^2/a^2+y^2/b^2=1, so that B is at (0,b), and line AC is parallel to the x-axis, as shown above. Also, foci F_1 and F_2 lie on sides line BC and line AB, respectively. Determine the value of AB/(length between F_1 and F_2).
