$$f\left(x\right)=-x-4$$

$$\int e^{-2}\cdot\cos\left(2x\right)dx$$

$$\left(1.1x+1.3y\right)\left(1.1x-1.3y\right)$$

$$29.8-88.1$$

$$ax+bx^2$$

$$\frac{x}{2x-3}+\frac{4}{x+1}=1$$

$$\lim_{x\to\infty}\left(\frac{4x^2+8}{3x^3+6}\right)$$