$5x-1=19$

$\left(6-1\right)^2+\left(2-\left(-4\right)\right)^2$

$2\cos\left(x\right)-\frac{1}{\cos\left(x\right)}$

$3\left(\frac{5}{-3}\right)$

$\frac{dy}{dx}=\frac{\left(x-18\right)y^6}{x^3\left(y^4-5\right)}$

$-\left(+3\:-\:2\:-\:1\right)\:+\:\left(-5\:+\:7\:+\:4\right)$

$103,5-43,7$