$$\frac{x^4+3}{x^2}$$

$$\frac{120}{\left(-8\right)}$$

$$+20\:+30\:+50\:-10$$

$$\left(\tan^2x+1\right)\left(\cos^2\left(-x\right)-1\right)=-\tan^2x$$

$$6x^5+x+5x^4+3x^2$$

$$\left(3x+1\right)\left(3x-4\right)$$

$$\int14\sin\left(3x\right)dx$$