$3x\:-\:t\:-\:2x\:\left(x\:-\:t\right)$

$\frac{dy}{dx}=\left(10x-7\right)$

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

$\lim_{x\to0}\left(e^{\frac{-1}{x^2}}\right)\left(\frac{1}{x^5}-\frac{3}{x^3}\right)$

$0,00028\:\cdot800.000$

$\sin x+3=2-\sin x$

$\frac{x^2+\frac{5}{3}x+1}{x-3}$