$$6-10-\left[8-\left\{2-\left(6-3\right)\right\}\right]$$

$$x^2-24x-36$$

$$\arcsin\left(\sin\left(\frac{7\pi}{4}\right)\right)$$

$$\lim_{x\to0}\left(\frac{1-\sec^3\:x}{1-cos\:x}\right)$$

$$x\frac{2}{5}x\frac{8}{5}$$

$$\left(-28\right)-\left(-15\right)-\left(+35\right)-\left(12\right)$$

$$a3\:+\:8$$