$3k=-7+3k$

$\lim_{x\to4}\left(\frac{x-256}{x-4}\right)$

$\frac{\csc\left(x\right)\cot\left(x\right)}{\sec\left(x\right)\tan\left(x\right)}$

$-6n+n+3n$

$\int\frac{x-1}{\sqrt{x^2-8x}}dx$

$\int_0^1\left(\frac{1}{\left(81-x^2\right)^{\frac{1}{2}}}\right)dx$

$\left(x\right)^3+\left(8\right)^3$