SI. 1 Let $A=15 \times \tan 44^{\circ} \times \tan 45^{\circ} \times \tan 46^{\circ}$, find the value of $A$.
Similar question 2012 FG2.1
$$
A=15 \times \tan 44^{\circ} \times 1 \times \frac{1}{\tan 44^{\circ}}=15
$$