<prompt> Ikiwa ei alpha frac35 frac45 i na ei beta -frac1213 frac513 i, kisha tafuta sin alpha beta.  <response>: Kuzidisha equations zilizotolewa, tunapataei alpha beta kushoto frac35 frac45 i kulia kushoto -frac1213 frac513 i kulia -frac5665 - frac3365 i.Lakini ei alpha beta cos alpha beta i sin alpha beta, hivyo sin alpha beta -frac3365. 