Prove that $(p\oplus q)\oplus r$ is logically equivalent to $p\oplus (q \oplus r)$
34768
Proving $(p \oplus q) \oplus r=p \oplus (q \oplus r)$
110662
Show that $P(\mathbb{N})$ is equivalent to $2^\mathbb{N}$
62936
Proving equivalencies of two versions of the Axiom of Choice
140194
Using natural deduction to prove that $p \implies q \vdash \lnot p \lor q$
41846
$(\mathbb{R}^n,\|\cdot\|_{p})$ is isometrically isomorphic to $(\mathbb{R}^n,\|\cdot\|_{q})$ iff $p=q,$
73526
The equivalence of "Every surjection has a right inverse" and the Axiom of Choice
148790
Basic question about proofs with the goal $\exists x P(x)$
61103
Prove that $\mathbb{|Q| = |Q\times Q|}$
45323
How to prove $\vdash\neg P\to (P\to Q)$?
21250
Prove $x \equiv a \pmod{p}$ and $x \equiv a \pmod{q}$ then $x \equiv a\pmod{pq}$
116215
Prove that $P(A \cap B\mid C)=P(A \mid (B \cap C))P(B\mid C)$
66548
proving topological equivalence
137511
Trying to show that $\sup \{b^p:p\in Q,\;0<p<x\} = \inf\{b^q:q\in Q,\;x<q\}$
91861
Propositional Logic: p → q, ¬p → r, ¬q → ¬r ⊢ q
116527
Validating a proof for necessary and sufficient conditions on sets A & B such that $P(A) \cup P(B) = P(A\cup B)$
62755
The simplest way of proving that $|\mathcal{P}(\mathbb{N})| = |\mathbb{R}| = c$
153634
A statment about the equivalence between the Axiom of Choice and the surjectivity of the projections.