[tex]a) \ sn(180^{o}-45^{o}) = sin45^{o} = \frac{\sqrt{2}}{2}\\\\c) \ tg(90^{o}+30^{o}) = -ctg30^{o} = -\sqrt{3}\\\\e) \ cos(180^{o}-60^{o}) = -cos60^{o} =-\frac{1}{2}\\\\b) \ sin(90^{o}+60^{o}) = cos60^{o}=\frac{1}{2}\\\\d) \ ctg(90^{o}+45^{o}) = -tg45^{o} = -1\\\\cos(180^{o}-30^{o}) = -cos30^{o} = \frac{\sqrt{3}}{2}[/tex]
