$$\left(x^2-x+1\right)\cdot\left(x^2+x+1\right)-1$$

$$-3a^2-b;\:a=1;\:b=-3$$

$$2x-5>-7$$

$$100+80y+16y^2$$

$$\frac{\left(1-\cos\left(x\right)^2\right)\left(1+\cot\left(x\right)^2\right)}{\cos\left(x\right)}=\sec\left(x\right)$$

$$12x^2-2x-4$$

$$\int\left(5x+12\right)e^{\frac{x}{7}}dx$$