Bantuin ya kawan, bahan buat ulangan...

3.
sin 60 = tinggi/15
√3/2 x 15 = tinggi
tinggi = 15√3/2
4.
[tex] \frac{ \frac{1}{2} + \frac{ \sqrt{3} }{2} + \frac{1}{2} }{ \frac{ \sqrt{2} }{2} - \frac{ \sqrt{3} }{2} } = \frac{2 + \sqrt{3} }{ \sqrt{2} - \sqrt{3} } = \frac{(2 + \sqrt{3} )( \sqrt{2} + \sqrt{3} )}{2 - 3} = - 3 - 2 \sqrt{2} - 2 \sqrt{3} - \sqrt{6} [/tex]
5.
(½+½)(½-½) =0