$\left(x^{n+1}+2x^{n+2}-x^{n-3}\right)\left(x^2+x\right)$

$\cos^4\left(x\right)\:\sec^3\left(x\right)$

$7^x+7^{x+1}+7^{x+2}=2793$

$\frac{dy}{dx}=\frac{6e^{2x}}{e^y},y\left(0\right)=0$

$\sqrt[6]{a^7}\cdot\sqrt[12]{x^5}$

$\lim_{x\to-\infty}\left(\frac{\ln\left(x^4+5\right)}{7x+1}\right)$

$\frac{1+\senx}{\cos x}+\frac{\cos x}{7+\senx}=2\sec x$