Calculus & analysis symbols 
Symbol Symbol Name Meaning / definition Example
limit limit value of a function  
ε epsilon represents a very small number, near zero ε 0
e e constant/ Euler's number e = 2.718281828... e = lim (1+1/x)x , x→∞
y ' derivative  derivative - Leibniz's notation (3x3)' = 9x2
y '' second derivative derivative of derivative (3x3)'' = 18x
y(n) nth derivative n times derivation (3x3)(3) = 18
  derivative  derivative - Lagrange's notation d(3x3)/dx = 9x2
second derivative derivative of derivative d2(3x3)/dx2 = 18x
nth derivative n times derivation  
time derivative derivative by time - Newton notation  
time second derivative derivative of derivative  
partial derivative   ∂(x2+y2)/∂x = 2x
integral  opposite to derivation  
double integral integration of function of 2 variables  
triple integral integration of function of 3 variables  
closed contour / line integral    
closed surface integral    
closed volume integral    
[a,b] closed interval [a,b] = {x | a x b}  
(a,b) open interval (a,b) = {x | a < x < b}  
i imaginary unit i ≡ √-1 z = 3 + 2i
z* complex conjugate z = a+biz*=a-bi z* = 3 + 2i
z complex conjugate z = a+biz = a-bi z = 3 + 2i
nabla / del gradient / divergence operator f (x,y,z)
vector    
unit vector    
x * y convolution  y(t) = x(t) * h(t)  
laplace transform  F(s) = {f (t)}  
Fourier transform X(ω) = {f (t)}  
δ delta function    
lemincate  infinity symbol