Simplify 2cos2xsin2x ?? how to do

i have to use trig identities to solve, confused.

1 Answer
Apr 20, 2018

You can simplify the expression to #sin(4x)#.

Explanation:

If we let #u=2x#, we can use the sine double angle formula backward:

#color(white)=2sin(2x)# #cos(2x)#

#=2sin(u)# #cos(u)#

#=sin(2u)#

#=sin(2*u)#

#=sin(2*2x)#

#=sin(4x)#

That's as simplified as it gets. Hope this helped!