Răspuns:
[tex] \frac{ \sqrt{2} }{2} - cos(45) \: + \: cos(60) \\ \frac{ \sqrt{2} }{2} - \frac{ \sqrt{2} }{2} + cos(60) \\ 0 + cos(60) \\ 0 + \frac{1}{2} \\ \frac{1}{2} = 0.5 \: care \: rotunjit \: inseamna \: 1[/tex]
