$$\frac{1}{2\sin\left(\frac{x}{2}\right)cos\left(\frac{x}{2}\right)}$$

$$\left(+12\right)-\:\left(-19\right)$$

$$\int x\:\sec^22x\:dx$$

$$x^2+3x+2x+6$$

$$\frac{1}{4}\cdot0+3$$

$$\left(x\:-\:5\right)\left(x\:+\:1\right)\:=\:2\left(x\:-\:2\right)^2$$

$$-\frac{3}{4}\left(-0.75\right)$$