Is #6sin(x)cos(x)# equivalent to #3sin(2x)# or #sin(3x)#?

1 Answer
May 1, 2017

The usual identity is:

#sin 2 x = 2 sin x cos x#

Therefore:

#alpha sin 2 x = 2alpha sin x cos x#

Or, reversing the order:

# 2alpha sin x cos x = alpha sin 2 x #

With #alpha = 3#, that becomes:

# 6 sin x cos x= 3 sin 2 x #