It means maths in a posher time of way numeracy. It also means something to do with figures (numbers)
Do you mean this symbol ∈ (or backwards 3) if so, it means is an element of; Also, ∉ (with strikethrough) (or backwards 3 with strikethrough) is the symbol for "is not an element of" used in set membership. See also Element (mathematics) and Set (mathematics)
If all the elements in set A are also elements of set B, then set A is a subset of set B.
A variance is a measure of how far a set of numbers is spread out around its mean.
The difference between the highest and lowest number in the set
A matrix in mathematics is a rectangular array of quantities or expressions set out by rows and columns.
A joint set is a dumb thing in the dumber thing mathematics
In mathematics, the range is the difference between the highest and lowest numbers in a set of data.
In mathematics it refers to a set of numbers which cannot be expressed as ratios of two integers.
Null set
The symbol "X" with a line over it is often used in mathematics to represent the average or arithmetic mean of a set of values. It is calculated by adding up all the values and dividing by the number of values in the set.
In mathematics and philosophy, the symbol "" represents the empty set, which is a set that contains no elements. It signifies a collection with nothing in it.
Yes the null set is a subset of every set.