Developer`ZeroQ

ZeroQ[expr] returns True if built-in transformations allow it to be determined that expr is numerically equal to zero, and returns False otherwise.

ZeroQ uses a combination of symbolic transformations and randomized numerical evaluation.

If ZeroQ[expr] returns False it does not necessarily mean that expr is mathematically not equal to zero; all it means is that built-in transformations did not allow this to be determined.

See also: ImpliesQ.