$$-9b^2+4b^2$$

$$-7y-2x+9z-8x+6y$$

$$\frac{x+1}{x+2}<-x-1$$

$$\tan-1=1$$

$$\frac{dy}{dx}\left(\:x\sqrt{x^2\:+\:41}\right)$$

$$\int\left(\sin\left(x\right)\tan\left(x\right)\right)dx$$

$$2\log_{16}\left(8\right)+2\log_{16}\left(2\right)$$