$$\frac{x+1}{\:2}+\frac{x+2}{3}+\frac{x+3}{4}\ge\:\frac{77}{4}$$

$$\lim_{x\to0}\left(\frac{\ln\left(1+sen4x\right)}{tanx}\right)$$

$$s^2-4s+29$$

$$\lim_{x\to\infty}\left(\frac{\sin\left(x+1\right)}{\sin\left(x\right)}\right)$$

$$x^2+81x$$

$$\frac{dy}{dx}=x-2y+12$$

$$7-3^2+4$$