I just need a confirmation on the question (picture): Do I just make so that that matrix times its transpose equal to 1 and solve it?

Question

wolfe8 · Answer

attachment

john_es · Answer

You need to check the two products, because the matrix product, in general, does not obey the commutation rule of the product.
$$Q^TQ=QQ^T=I$$
The two first products must be satisfied.

wolfe8 · Answer

So... I have to check it for both ways? And I think I meant the identity, not 1. Alright I'll do that. Thanks!

john_es · Answer

Yes, but this time you'll have no problem. The two products give the same results. ;)

wolfe8 · Answer

Ok just to confirm that I got it right, does alpha have to be either positive or negative 1/2 or 0?