Is it possible to reduce the division of ARCTAN over ARCTAN?
I'm interested in having a simplified formula that calculates the ratio of one angle over another, given two lines connected between three sets of coordinates on a Cartesian plane.
That ratio, as I've been able to determine thus far, is ARCTAN(y2-y1/x2-x1) / ARCTAN(y3-y1/x3-x1). I'm interested in whether this can be somehow reduced. I've been unable to determine if there's a trigonometric identity that can help simplify this, or if the coordinates within the trig functions themselves could be reduced somehow. I'm not terribly savvy with math.