nilai dari cos 30 + cos 45 +cos 60

[tex]cos \: 30 + cos \: 45 \: + cos \: 60 \\ = \frac{1}{2} \sqrt{3} + \frac{1}{2} \sqrt{2} + \frac{1}{2} \\ = \frac{ \sqrt{3 } + \sqrt{2} + 1 }{2} [/tex]