Question

write rotation matrix for a rotation angle 30°?​

Answer 1

Explanation:

Construct the matrix for a rotation of a vector around the x- axis by 30°. Then let ... The rotation angle is positive if the rotation is in the counter-clockwise direction when viewed by an .

Answer 2

Explanation:

The simplest way to find the rotation angle is to take the trace of the matrix, the sum of the diagonal elements. By Cameron Buie's answer this equals 1+2cos(θ) where θ is the angle of rotation. θ can then be determined up to sign which will depend on the orientation of the axis of rotation chosen.