$\left(5x+3y\right)\left(2x-3y\right)$

$\frac{cos2x+senx+1}{2senx+1}=senx$

$\frac{d^2}{dx^2}\left(a\sin\left(cf\right)+b\cos\left(cf\right)\right)$

$-\frac{n}{6}=11$

$\frac{y^9\left(y^3x^{-2}\right)^{-3}}{\left(5y^2\right)^4x^2}$

$5^4+5^{-1}\cdot5^2\cdot5^{-3}$

$5x-9-9x^2-3x-5$