What is the y-intercept of `f(x)=4^x` ?

Hello!

By definition, the y-intercept of a function (or its graph) is the ordinate (y-coordinate) of a point where the graph intersects the y-axis.

For one-valued function g it is g(0), if g is defined at x=0. Our function f is one-valued and defined at 0, and `f(0)=4^0=1,` because anything except 0 at the degree 0 is 1.

Thus the answer is: the y-intercept of f(x) is 1.

That said, f has no x-intercepts because `4^x` always greater than zero.