Input:
`definition(Phi(x))`
Compute:
$$$$definition:
$$Phi(x)$$
Result:
$$\frac{1}{2}+\frac{1}{2}\ erf(0.7071067811865476\ x)$$
LaTeX:
\frac{1}{2}+\frac{1}{2}\ erf(0.7071067811865476\ x)
$$$$definition:
$$Phi(x) == \frac{1}{2}+\frac{1}{2}\ erf(0.7071067811865476\ x)$$