$$\int_r^{3r}\frac{8}{r^3}dr$$

$$\lim_{x\to1}\left(\frac{1-x}{ln^2\left(x\right)}\right)$$

$$\left(\frac{3}{2}x^3-\frac{2}{5}y^2\right)^2$$

$$\left(-13\right)\left(10\right)\left(-15\right)$$

$$\log\left(x\right)+\log\left(x+3\right)=2\cdot\log\left(x+1\right)$$

$$56x-14x^2+21x^3$$

$$4x+9<5x-1$$