Question: are piecewise functions one to one?
Answer: 2 Answers. This function is not one-to-one, since f(0)=f(−1)=0. The definition of a one-to-one function (also called injective sometimes) is that two different inputs are mapped to two different outputs. ... Whether or not the function is defined by a formula, piecewise, not continuous, or polynomial... it does not matter.