$7mn\frac{3x}{7}-1$

$\frac{n^8\left(x+8\right)^n}{\left(7^n\right)\left(n^{\frac{26}{3}}\right)}$

$\int\frac{3}{\left(\sqrt{81-x^2}\right)}dx$

$a^3+12a^2+48a+64$

$\lim\:_{x\to\:\:25}\frac{x-25}{\sqrt{x}-5}$

$f\left(x\right)=2x^{-4}+4x^2-2x^5$

$\left(x\right)\:+\:\left(2y\right)^2$