$\frac{\sin\left(\theta\right)}{\sin\left(\theta\right)-\cos\left(\theta\right)}=\frac{1}{1-\cot\left(\theta\right)}$

$x-6>26$

$x^2-4x^2-21$

$\lim_{x\to1}\frac{\sin\left(\pi x\right)}{\sin\left(3\pi x\right)}$

$\frac{dy}{dx}=\frac{-x}{y},y\left(4\right)=3$

$-x^2-11x-10>0$

$2a\sqrt{3a}$