Question

(sin 60° cos 30° − cos 60° sin 30°) = ?
(a) 0
(b) 1
(c) $\frac{1}{2}$
(d) $\frac{\sqrt{3}}{2}$

Answer 1

(c)$\frac{1}{2}$

$$\begin{gathered} \sin {60}^{\mathrm{o}}\cos {30}^{\mathrm{o}}-\cos {60}^{\mathrm{o}}\sin {30}^{\mathrm{o}} \\ =\left(\frac{\sqrt{3}}{2}\times \frac{\sqrt{3}}{2}-\frac{1}{2}\times \frac{1}{2}\right) \\ =\frac{3}{4}-\frac{1}{4} \\ =\frac{2}{4}=\frac{1}{2} \end{gathered}$$