2sin8x
EDIT: Remember that 2sinxcosx = sin2x (this is just an identity).
So you have 2*2sin(4x)cos(4x). If you let u=4x then you have
2*2sinucosu = 2sin(2u) = 2sin(2*4x) = 2sin(8x)
EDIT: Remember that 2sinxcosx = sin2x (this is just an identity).
So you have 2*2sin(4x)cos(4x). If you let u=4x then you have
2*2sinucosu = 2sin(2u) = 2sin(2*4x) = 2sin(8x)