Question 1029580
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Help, please!!!  I am supposed to circle all expressions that are equivalent to sin 4a.  options are:

A) 4 sin a cos a
B) 2 sin 2a cos 2a
C) 4 sin a cos a-8 sin^3 a cos a
D) 4 sin a cos a cos 2a
E) sin a cos 3a-cos a sin 3a
F) 4 sin a cos^3 a-4 sin^3 a cos a

I know the last one is equal to 4a, but I'm not sure if this is the only one or not.  Thanks for any help!
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Options B), D), F)