# is co-NP-hard contained in EXPTIME-hard or vice-versa?

is co-NP-hard contained in EXPTIME-hard or vice-versa?

• What is EXPTIME-hard? It's always good to include the definition of possibly obscure terms so that your question is self-contained. – Kyle Jones Jun 10 '20 at 17:47

It is known that co-NP $$\subseteq$$ PSPACE $$\subseteq$$ EXPTIME, so every EXPTIME-hard problem, must also be a co-NP-hard problem (as there is a polynomial time reduction from every $$L\in$$ EXPTIME to it, and therefore also from every $$L\in$$ co-NP)
Therefore EXPTIME-hard $$\subseteq$$ co-NP-hard.