Recent content by delta_epsilon

So are you saying blinktx411 solution is incorrect?

Homework Statement Suppose f: ℝ → ℝ takes on each of its values exactly twice; that is, for each y in ℝ, the set {x: y = f(x)} has either 0 or 2 elements. Show that f is discontinuous at infinitely many points. Homework Equations I don't know if this is relevant, but in the prior text to...