Question

1 select the correct answer from each drop - down menu. the product of sin 30° and sin 60° is same as the product of and

Explanation:

Step1: Recall sine - values

We know that $\sin30^{\circ}=\frac{1}{2}$ and $\sin60^{\circ}=\frac{\sqrt{3}}{2}$. So, $\sin30^{\circ}\times\sin60^{\circ}=\frac{1}{2}\times\frac{\sqrt{3}}{2}=\frac{\sqrt{3}}{4}$.

Step2: Recall co - function identity

The co - function identity states that $\sin\alpha=\cos(90^{\circ}-\alpha)$. So, $\sin30^{\circ}=\cos60^{\circ}=\frac{1}{2}$ and $\sin60^{\circ}=\cos30^{\circ}=\frac{\sqrt{3}}{2}$. And $\sin30^{\circ}\times\sin60^{\circ}=\cos60^{\circ}\times\cos30^{\circ}$.

Answer:

$\cos60^{\circ}$, $\cos30^{\circ}$