< #5.5.0 Smtp;554 Sorry, Message Looks Like Spam To Me> Cos (A) = Root 5/5, 0<a<Pi/2. How Do I Solve?

Cos (A) = root 5/5, 0<a<Pi/2. How do I solve? - < #5.5.0 smtp;554 sorry, message looks like spam to me>

In addition, Sin (B) = -4 / 5, pi / 2 \\ \\ \\ \\ \\ \\ \\ \\ b u0026lt \\ \\ \\ \\ \\ \\ \\ \\ u0026lt, 0