I am trying to build a rotational transformation matrix both for counterclockwise and clockwise angles. The first matrix in the picture is for counterclockwise angles and the second one for clockwise angles. The first matrix I built corresponds to the one given in my linear algebra book so it seems the building process's OK. However, in my book there isn't one for clockwise angles and that's why I've built one. I've been searching on the Internet and it seems that the rotational matrix for clockwise angles is the same as the one for counterclokwise ones but with the sines with opposite signs. Nevertheless, that's not the one I've obtained If I thry for example with a 24.78 clokwise angle. So, where does my reasoning fail? Thanks!