3.5.6 Intersection of a 2D graph with the axis

The ordinate of the intersection of the graph of f with the
yaxis is returned by :
f(0)
indeed the point of coordinates (0,f(0)) is the intersection point of the
graph of f with the yaxis,
 Finding the intersection of the graph of f with the xaxis
requires to solve the equation f(x)=0.
If the equation is polynomiallike, solve will find
the exact values of the abscissa of these points. Input:
solve(f(x),x)
Otherwise, we can find numeric approximations of these
abscissa. First look at the graph for an initial guess or a
range with an intersection and refine with fsolve.