If you are not a native English speaker, some time it’s a bit challenging for you to remember the functions to use in Excel, or in programming.

Understanding their original meaning might help you to remember them easier. Let’s start with the most basic ones

Set

ℕ: Natural number

ℤ: Integer number

ℚ: Rational number

Irrational number

ℝ: Real number

ℂ: Complex number

Numbers

• prime number: a natural number, formed by multiplying two smaller natural number
• square number:is the square of an integer, is a product of some integer with itself
• perfect number: equal to the sum of its positive divisors

Fractions

• dividend/divisor=quotient+remainder
• fraction = numerator/denominator
• mixed fraction = integer + fraction
• modulus: find the remainder of the division

Function

• abs: absoulte value
• sqrt: square root
• pow: power
• factorial(n!)
• inverse (1/x)

Constants

pi: 3.14159…

e: euler number (2.71828…)