title: Why is P ⊆ co-NP?
body: <p>I've seen several places that have simply stated that it's known that P is a subset of the intersection of NP and co-NP. Proofs that show that P is a subset of NP are not hard to find. So to show that it's a subset of the intersection, all that's left to be done is show that P is a subset of co-NP. What might a proof of this be like? Thank you much!</p>