for unit quaternions used to represent rotations for 3D provethat :
a) quaternion conjugate corresponds to rotation inverse (Approach 1: negate the angle in the formula for converting from theaxis-angle form and apply trigonometric identities. Approach 2:convincingly discusses what negating and axis description does interms of rotation effects and in terms of the formula)
b) negated quaternions represent the same rotation ( hint: add2PI to the rotation angle in the axis angle formula, explain whatthat means in terms of orientation, and apply trigonometricidentities
