14. Which of the following is equal to $\left(\sin 60^{\circ} \sin 30^{\circ}\right)-\left(\cos 30^{\circ} \cos 60^{\circ}\right)$ ?
I. $1 / 2$
II. 1
III. 0
IV. $\sqrt{2}$
A. I only
B. II only
C. III only
D. IV only

Answer

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Answer

The result is very close to 0, so the final answer is $\boxed{0}$

Steps

Step 1 ：Calculate the value of $\left(\sin 60^{\circ} \sin 30^{\circ}\right)-\left(\cos 30^{\circ} \cos 60^{\circ}\right)$

Step 2 ：The result is very close to 0, so the final answer is $\boxed{0}$