Question #f676d
1 Answer
Oct 19, 2016
We will use the double angle identities
-
#sin(2theta) = 2sin(theta)cos(theta)# -
#cos(2theta) = 1-2sin^2(theta) = cos^2(theta)-sin^2(theta) = 2cos^2(theta)-1#
Proceeding...
#= 1/2(2sin(2x)cos(2x))#
#=sin(2x)cos(2x)#
#=(2sin(x)cos(x))(1-2sin^2(x))#
#=2sin(x)cos(x)(1) - (2sin(x)cos(x))(2sin^2(x))#
#=2sin(x)cos(x) - 4sin^3(x)cos(x)#
