Question
Evaluate the following:
$\frac{\sin21^\circ}{\cos69^\circ}$
$\frac{\sin21^\circ}{\cos69^\circ}$
✓
Answer
$\frac{\sin21^\circ}{\cos69^\circ}=\frac{\sin(90-69^\circ)}{\cos69^\circ}$
$=\frac{\cos69^\circ}{\cos69^\circ}$
$=1$
$=\frac{\cos69^\circ}{\cos69^\circ}$
$=1$
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