Index
 Greek letters in math and science
 Doublestruck capital letters in math
 Constants
 Table of set theory symbols
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Greek letters in math and science
You find hese symbols my equation page.
I took this from Wiki and adjusted it with comments that I find useful.
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Symbol  Name 
Formula 

Αα  Alpha  
Ββ  Beta  
Χχ  Chi  
Εε  Epsilon  
Δ δ=  Delta  
Ηη  Eta  
δ  Kronecker delta  EFE Einstein Field equations. 

∂ 
Curly d  In partial derivatives 

Gamma 


Ιι  Iota  .  
H_{0}  Hubble constant  Hubble flow v = H_{0}D, with H_{0} , the constant of proportionality Hubble constant 

Κκ  Kappa  
Λλ  Lambda  Λ“Einstein’s cosmological constant, is the energy density of space, or vacuum energy, that arises in Albert Einstein’s field equations of general relativity. It is closely associated to the concept of dark energy. In 1931 Einstein finally accepts the theory of an expanding universe…”) Wiki “Λ=2.036×10−35 s−2. This value of Λ is in excellent agreement with the measurements recently obtained by the HighZ Supernova Team and the Supernova Cosmology Project.” scitation.org  
Μμ  Mu  
Νν  Nu  
Οο  Omicron  
Ωω  Omega  
Ππ  Pi
(product) 

Φφ  
Ψψ  Psi  
Ρρ  Rho  
Ζζ  Zeta  

Re. = Ramanujan summation. 
Ramanujan summation. ( Wiki ) 

Σσ 
Sigma 


Ττ  Tau  
Θθ  Theta  
Ξξ  Xi  
Υυ  Upsilon  
Zeta 
ζ(s) = 1 + 1/2^{s} + 1/3^{s} + 1/4^{s} + … Riemann’s zeta function 

~  About  
!  factorial  4!=4*3*2*1  
≠ 
not equal  
∞ 
infinity  
∫  Integral 

Source: Wiki
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Doublestruck capital letters in math
Source: http://xahlee.info/comp/unicode_math_font.html
Meaning in Math
 ℤ → integers.
 ℕ → natural numbers.
 ℙ → primes.
 ℚ → be rational.
 ℝ → get real.
 ℂ → complex number.
 ℍ → quaternions.
 → sedenions.
 ℑ → imaginary part
 ℜ → real part
 ⅅ → Derivative
 ⅆ → Differential
 ⅇ → euler’s number (natural growth number)
 ⅈ → imaginary unit.
 ⅉ → notation used by engineers for ⅈ
 ℵ → cardinality of infinite sets.
 ℭ → continuum
Constants
Most information has been taken from
https://www.forbes.com/sites/ethansiegel/2015/08/22/ittakes26fundamentalconstantstogiveusouruniversebuttheystilldontgiveeverything/#2174185a4b86 that links to Wikipedia
Physical constants
C  Value 
Name  Formula 
C  299.792.458 m/s ~300.000 km/s 
Speed of light  E=mc^{2}

6.62607015×10^{−34} J⋅s^{}  Plancks constant
“to calculate the energy of the electromagnetic wave” 
E=hf


k_{B}  1.38065 × 10^{−23} J/K  Boltzmann constant
Boltzmanns entropy formula 

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Table of set theory symbols
Taken and adapted from www.rapidtables.com
Symbol  Symbol Name  Meaning / definition 
Example 

{ }  set  a collection of elements  A = {3,7,9,14}, B = {9,14,28} 
  such that  so that  A = {x  x∈, x<0} 
A⋂B  intersection  objects that belong to set A and set B  A ⋂ B = {9,14} 
A⋃B  union  objects that belong to set A or set B  A ⋃ B = {3,7,9,14,28} 
A⊆B  subset  A is a subset of B. set A is included in set B.  {9,14,28} ⊆ {9,14,28} 
A⊂B  proper subset / strict subset  A is a subset of B, but A is not equal to B.  {9,14} ⊂ {9,14,28} 
A⊄B  not subset  set A is not a subset of set B  {9,66} ⊄ {9,14,28} 
A⊇B  superset  A is a superset of B. set A includes set B  {9,14,28} ⊇ {9,14,28} 
A⊃B  proper superset / strict superset  A is a superset of B, but B is not equal to A.  {9,14,28} ⊃ {9,14} 
A⊅B  not superset  set A is not a superset of set B  {9,14,28} ⊅ {9,66} 
2^{A}  power set  all subsets of A  
power set  all subsets of A  
A=B  equality  both sets have the same members  A={3,9,14}, B={3,9,14}, A=B 
A^{c}  complement  all the objects that do not belong to set A  
A’  complement  all the objects that do not belong to set A  
A\B  relative complement  objects that belong to A and not to B  A = {3,9,14}, B = {1,2,3}, A \ B = {9,14} 
AB  relative complement  objects that belong to A and not to B  A = {3,9,14}, B = {1,2,3}, A – B = {9,14} 
A∆B  symmetric difference  objects that belong to A or B but not to their intersection  A = {3,9,14}, B = {1,2,3}, A ∆ B = {1,2,9,14} 
A⊖B  symmetric difference  objects that belong to A or B but not to their intersection  A = {3,9,14}, B = {1,2,3}, A ⊖ B = {1,2,9,14} 
a∈A  element of, belongs to 
set membership  A={3,9,14}, 3 ∈ A 
x∉A  not element of  no set membership  A={3,9,14}, 1 ∉ A 
(a,b)  ordered pair  collection of 2 elements  
A×B  cartesian product  set of all ordered pairs from A and B  
A  cardinality  the number of elements of set A  A={3,9,14}, A=3 
#A  cardinality  the number of elements of set A  A={3,9,14}, #A=3 
  vertical bar  such that  A={x3<x<14} 
≡  congruency  3 is cogruent to 15 in modulo 12 (modular arithmetic) 
3 ≡ 15 (mod12) 
ℵ_{0}  alephnull  infinite cardinality of natural numbers set  
ℵ_{1}  alephone  cardinality of countable ordinal numbers set  
Ø  empty set  Ø = {}  A = Ø 
universal set  set of all possible values  
ℕ_{0}  natural numbers / whole numbers set (with zero)  _{0} = {0,1,2,3,4,…}  0 ∈ _{0} 
ℕ_{1}  natural numbers / whole numbers set (without zero)  _{1} = {1,2,3,4,5,…}  6 ∈ _{1} 
ℤ  integer numbers set  = {…3,2,1,0,1,2,3,…}  6 ∈ 
ℚ  rational numbers set  = {x  x=a/b, a,b∈ and b≠0}  2/6 ∈ 
ℝ  real numbers set  = {x  ∞ < x <∞}  6.343434 ∈ 
ℂ  complex numbers set  = {z  z=a+bi, ∞<a<∞, ∞<b<∞}  6+2i ∈ 