{
 "source": "https://peabody.kids/flashcards/math-symbols",
 "id": "math-symbols",
 "title": "Math Symbols and Their Names",
 "category": "math",
 "subject": "Math",
 "levels": [
  "3-5",
  "6-8",
  "9-12",
  "college"
 ],
 "description": "Common math symbols and what each one means.",
 "tags": [
  "symbols",
  "notation"
 ],
 "frontLabel": "Symbol",
 "backLabel": "Name and meaning",
 "cards": [
  [
   "+",
   "Plus: add"
  ],
  [
   "−",
   "Minus: subtract"
  ],
  [
   "×",
   "Times: multiply"
  ],
  [
   "÷",
   "Divided by: divide"
  ],
  [
   "=",
   "Equals: is the same value as"
  ],
  [
   "≠",
   "Is not equal to"
  ],
  [
   "<",
   "Is less than"
  ],
  [
   ">",
   "Is greater than"
  ],
  [
   "≤",
   "Is less than or equal to"
  ],
  [
   "≥",
   "Is greater than or equal to"
  ],
  [
   "≈",
   "Is approximately equal to"
  ],
  [
   "≡",
   "Is identical to or congruent (mod) to"
  ],
  [
   "±",
   "Plus or minus"
  ],
  [
   "∓",
   "Minus or plus"
  ],
  [
   "√",
   "Square root (radical)"
  ],
  [
   "∛",
   "Cube root"
  ],
  [
   "π",
   "Pi: about 3.14159, circumference over diameter"
  ],
  [
   "∞",
   "Infinity: unbounded, without end"
  ],
  [
   "%",
   "Percent: out of 100"
  ],
  [
   "‰",
   "Per mille: out of 1,000"
  ],
  [
   "°",
   "Degree: a unit of angle or temperature"
  ],
  [
   "′",
   "Prime: minutes, feet, or a related variable"
  ],
  [
   "″",
   "Double prime: seconds, inches"
  ],
  [
   "|x|",
   "Absolute value of x"
  ],
  [
   "!",
   "Factorial"
  ],
  [
   "Σ",
   "Sigma: sum of a series"
  ],
  [
   "Π (capital pi)",
   "Product of a series"
  ],
  [
   "Δ",
   "Delta: change in"
  ],
  [
   "∂",
   "Partial derivative"
  ],
  [
   "∫",
   "Integral"
  ],
  [
   "∮",
   "Contour or closed-loop integral"
  ],
  [
   "lim",
   "Limit"
  ],
  [
   "θ",
   "Theta: commonly an angle"
  ],
  [
   "λ",
   "Lambda: wavelength, eigenvalue"
  ],
  [
   "μ",
   "Mu: mean of a population"
  ],
  [
   "σ",
   "Sigma (lowercase): standard deviation"
  ],
  [
   "ε (epsilon)",
   "A very small positive number in limits"
  ],
  [
   "φ",
   "Phi: the golden ratio (about 1.618) or an angle"
  ],
  [
   "e",
   "Euler's number, about 2.71828"
  ],
  [
   "i",
   "Imaginary unit, where i² = −1"
  ],
  [
   "ℝ",
   "The set of real numbers"
  ],
  [
   "ℚ",
   "The set of rational numbers"
  ],
  [
   "ℤ",
   "The set of integers"
  ],
  [
   "ℕ",
   "The set of natural numbers"
  ],
  [
   "ℂ",
   "The set of complex numbers"
  ],
  [
   "∈",
   "Is an element of"
  ],
  [
   "∉",
   "Is not an element of"
  ],
  [
   "⊂",
   "Is a subset of"
  ],
  [
   "∪",
   "Union: in either set"
  ],
  [
   "∩",
   "Intersection: in both sets"
  ],
  [
   "∅",
   "Empty set: no elements"
  ],
  [
   "∀",
   "For all"
  ],
  [
   "∃",
   "There exists"
  ],
  [
   "∴",
   "Therefore"
  ],
  [
   "∵",
   "Because"
  ],
  [
   "⇒",
   "Implies"
  ],
  [
   "⇔",
   "If and only if"
  ],
  [
   "∥",
   "Is parallel to"
  ],
  [
   "⊥",
   "Is perpendicular to"
  ],
  [
   "∠",
   "Angle"
  ],
  [
   "△",
   "Triangle"
  ],
  [
   "≅",
   "Is congruent to"
  ],
  [
   "∼",
   "Is similar to"
  ],
  [
   "∝",
   "Is proportional to"
  ],
  [
   "f(x)",
   "Function f of x"
  ],
  [
   "f⁻¹",
   "Inverse function of f"
  ],
  [
   "n!",
   "n factorial: product of 1 to n"
  ],
  [
   "a:b",
   "Ratio of a to b"
  ],
  [
   "⌊x⌋",
   "Floor: greatest integer not above x"
  ],
  [
   "⌈x⌉",
   "Ceiling: least integer not below x"
  ],
  [
   "mod",
   "Modulo: the remainder after division"
  ],
  [
   "·",
   "Dot: multiplication"
  ],
  [
   "→ (arrow)",
   "Approaches, or maps to"
  ]
 ]
}