Answer:
C) -8cos 3xsin x
Step-by-step explanation:
To express -4(sin4x - sin2x) as a product, we use the formula sinA - sinB = 2cos[(A + B)/2]sin[(A - B)/2.
Comparing sin4x - sin2x with sinA - sinB, A = 4x and B = 2x.
Substituting these into the equation, we have
sin4x - sin2x = 2cos[(4x + 2x)/2]sin[(4x - 2x)/2
sin4x - sin2 x = 2cos[6x/2]sin[2x/2]
sin4x - sin2x = 2cos3xsinx
So, -4(sin4x - sin2x) = -4(2cos3xsinx) = -8cos3xsinx
So, -4(sin4x - sin2x) = -8cos3xsinx
Thus, the answer is C
