$\frac{tan\left(x\right)+cot\left(x\right)}{sin\left(x\right)+cot\left(x\right)\cdot cos\left(x\right)}$

$x^3\left(2+x^2\right)^5$

$\lim_{x\to\infty}\left(1-\frac{1}{x}\right)^{\frac{x}{9}}$

$\int4x^3sin\left(2x\right)dx$

$\left(2x+1\right)^3-\left(8x+3\right)^2$

$7y-21$

$\frac{4^9}{4^6}$