$\left(a+1\right)\cdot\left(a+6\right)$

$\frac{d}{dx}\left(y=tan\left(5^{3x^2}\right)\right)$

$4x^2+8x+1=5$

$\int x^2\left(x^4-1\right)^3dx$

$\lim_{x\to0}\left(1+\sin\left(2x\right)\right)$

$\frac{d}{dx}\left(4x^2y^3+1\right)^2$

$\lim_{x\to0}\left(\frac{1-cos2x}{x}\right)$