$-2^2-4$

$\frac{dy}{dx}=\frac{8x^5-6y}{x}$

$\lim_{x\to\infty}\left(1+\frac{5}{x}\right)^{\frac{x}{15}}$

$3\cos^2x+\cos x$

$\left(\sqrt[9]{81}\right)^{18}$

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

$x^2-1.2x+0.360$