Expand $\tan\left(\theta-x\right)$tan(θ−x).

Expand $\sin\left(3x-y\right)$sin(3x−y), rewriting it in terms of angles $3x$3x and $y$y.

Consider the following.

Expand $\cos\left(2x+3y\right)$cos(2x+3y), rewriting it in terms of angles $2x$2x and $3y$3y.

Manipulate trigonometric expressions

Apply trigonometric methods in solving problems