Wolfram Language & System 10.0 (2014)|Legacy Documentation

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TautologyQ

TautologyQ[bf]
gives True if all combinations of values of variables make the Boolean function bf yield True.

TautologyQ[expr,{a1,a2,}]
gives True if all combinations of values of the make the Boolean expression expr yield True.

ExamplesExamplesopen allclose all

Basic Examples  (2)Basic Examples  (2)

Test whether Boolean expressions are always true:

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Test whether pure Boolean functions are always true:

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Introduced in 2008
(7.0)