What is the equation for a graph that is shaped like a "w" but it has no pointy points, it is curvy?

thank you

1 answer

If it is shaped like a "w" but has no "points" (slope discontinuities), it must be "curvy".

There is more than one equation for such a curve. One of the simpler forms would be a fourth order polynomial, such as
(x-a)(x-b)(x+a)(x+b) = 0