Is it possible to represent the following function with a single formula, without using conditions? If not, how to prove it?
$F(x) = \begin{cases}u(x), & x \le 0, \ v(x) & x > 0 \end{cases}$
So that it will become something like that: $F(x) = G(x)$ With no conditions?
I need it for further operations like derivative etc.
What operations are allowed in the formula?
$$G(x) = \frac{x + |x|}{2x} v(x) + \frac{x - |x|}{2x} u(x)$$ will work (away from 0), but any "trick" along these lines is not going to help make taking derivatives any easier.