$$8\cos\left(23w\right)\sin\left(19w\right)$$

$$x^2-9=8x$$

$$-12x-48$$

$$\frac{1}{1+\tan\left(x\right)}+\frac{1}{1-\tan\left(x\right)}$$

$$\frac{2x-6}{\sqrt{x-2}-1}$$

$$\left(x+2y\right)dx-xdy=0$$

$$\left(2+3\right)\left(12\right)$$