Returns the cosine of this chord angle. This method is more efficient than converting to Angle and performing the computation.
cos(2A) = cos^2(A) - sin^2(A) = 1 - 2sin^2(A)
Returns the cosine of this chord angle. This method is more efficient than converting to Angle and performing the computation.
cos(2A) = cos^2(A) - sin^2(A) = 1 - 2sin^2(A)