$$\lim_{x\to0}\left(\frac{1-\cos\left(3x\right)}{\sin\left(4x\right)}\right)$$

$$\frac{dy}{dx}=\left(600-\sqrt{x^2+80}\right)\left(x\right)$$

$$8x^2+5x=0$$

$$\int\left(1-9x\right)^2dx$$

$$\int\left(1-x\right)^9dx$$

$$\int\frac{1}{\sqrt{x^2-64}}dx$$

$$4x^3\cdot0.5x^2-3x-1$$