A hidden zero is a quantity that is identically equal to zero but for which it is nontrivial to construct a proof of equality. Hidden zeros can be problematic for computer algebra systems. For example, failing to detect a hidden zero in a denominator can lead to symbolic expressions that are invalid because they contain division by 0. In the Wolfram Language, simple hidden zeroes such as (1 - e)^2 - e^2 + 2e - 1 (1 - π)^2 - π^2 + 2π - 1 do not automatically evaluate to 0, but functions such as Simplify and FunctionExpandcan reduce them to 0.

almost integer | constant problem | equal | identically zero | Richardson's theorem | uniformity conjecture | zero