Convert the following into a sum or difference of trigonometric functions.
\sin\left(\dfrac{3}{4}x\right) \cdot \cos\left(\dfrac{5\pi}{8}x\right)
.
\cos\left(2x\right)\sin\left(4x\right)\cos\left(4x\right)
.
\sin\left(2x\right)\sin\left(4x\right)
.
-\sin\left(3x\right)\sin\left(x\right)
\cos\left(\dfrac{x}{2}\right)\cos\left(\dfrac{3x}{2}\right)
\sin\left(\dfrac{x}{2}\right)\cos\left(\dfrac{x}{3}\right)
.
\dfrac{\sqrt{3}}{2}\cos\left(\dfrac{x}{3}\right)
.