I would just like to start off by saying the problem comes from Intro to electrodynamics, 3rd edition, griffiths. the problem is number 1.9. Question: Find the transformation matrix R that descries a rotation by 120 degrees about an axis from the origin through the point (1,1,1) the rotation is clockwise as you look down at the axis from the origin. 1. The problem statement, all variables and given/known data A(bar)x=Az A(bar)z=Ay A(bar)y=Ax 2. Relevant equations Transformation law = A(bar)x Rxx Rxy Rxz Ax A(bar)y = Ryx Ryy Ryz Ay A(bar)z Rzx Rzy Rzz Az 3. The attempt at a solution I know that the solution is R= 0 0 1 1 0 0 0 1 0 I am confused on how you get this? I have been trying to figure this out for a while. I know that i am over looking something here because it should be a very simple problem to do... I have been looking at this problem for a long period of time... I DO HAVE THE ANSWER KEY TO THE BOOK AND I DO HAVE CRAMSTER; I JUST CANNOT FIGURE OUT HOW TO GET THIS ANSWER... SOMEONE PLEASE HELP ME OUT! The answers that the answer key and Cramster provide as missing information to the point where I cannot follow what has occurred.