Mathematics and Logic Symbols ✍️ Quantifiers and Sets: ∀ - For all (universal quantifier) ∃ - There exists (existential quantifier) ∈ - Element of ∉ - Not element of ⊂ - Subset of ⊆ - Subset or equal ⊇ - Superset or equal ⊄ - Not a subset of ∪ - Union ∩ - Intersection ∪̸ - Not a subset ∅ - Empty set ∖ - Set difference Logical Operators: ⇒ - Implies ⇔ - If and only if (equivalence) ∧ - Logical AND ∨ - Logical OR ¬ - Negation ⊤ - True ⊥ - False ⊕ - Exclusive OR (XOR) → - Conditional implication ≡ - Equivalent Numbers and Constants: ℕ - Set of natural numbers ℤ - Set of integers ℚ - Set of rational numbers ℝ - Set of real numbers ℂ - Set of complex numbers ∞ - Infinity π - Pi e - Euler’s number Operations and Relations: ∑ - Summation ∏ - Product √ - Square root |x| - Absolute value of x Δ - Change/difference ∇ - Gradient ⊗ - Tensor product ≤ - Less than or equal to ≥ - Greater than or equal to ≠ - Not equal to ≈ - Approximately equal ∝ - Proportional to Geometric Symbols: ∡ - Angle ⊥ - Perpendicular ∥ - Parallel Reasoning and Statements: ∴ - Therefore ∵ - Because