$\frac{dy}{dx}=e^{5y+4x}$

$\ln\left(\frac{1+\tan\left(x\right)}{\tan\left(x\right)}\right)$

$2x^2+12x-5=0$

$\lim_{x\to0}\left(\frac{2x^2-3x}{x^2+x}\right)$

$3x<21$

$\lim_{x\to\frac{\pi}{4}}\left(\frac{\left(\sin\left(x\right)-1.\cos\left(x\right)\right)}{\tan\left(x\right)-1}\right)$

$7m^2-m^2+3n-\left(5-n\right)-\left(-3+m^2\right)-\left(2n+3\right)$