Korzystamy ze wzorów redukcyjnych:
[tex]sin120^{o} = sin(180^{o}-60^{o}) = sin60^{o}\\\\tg135^{o} = tg(180^{o}-45^{o}) = -tg45^{o}[/tex]
[tex]sin120^{o}+tg135^{o} = sin(180^{o}-60^{o})+tg(180^{o}-45^{o}) = sin60^{o}-tg45^{o} = \frac{\sqrt{3}}{2}-1[/tex]
