#### Answer

$3\rightarrow B$

#### Work Step by Step

$2\sin \alpha \cos \alpha =\sin 2\alpha \Rightarrow 2\sin 22.5\cos 22.5=\sin \left( 2\times 22.5\right) =\sin 45=\dfrac {\sqrt {2}}{2}$
$3\rightarrow B$

Published by
Pearson

ISBN 10:
013421742X

ISBN 13:
978-0-13421-742-0

$3\rightarrow B$

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