What is the definition of combination in math?

In mathematics, combinations and permutations are normally studied at the same time because they are very similar. But while a combination is a collection of the objects where the order doesn't matter, a permutation is an arrangement of a group of objects where the order does matter.

Likewise, people ask, what does it mean by linear combination?

In mathematics, a linear combination is an expression constructed from a set of terms by multiplying each term by a constant and adding the results (e.g. a linear combination of x and y would be any expression of the form ax + by, where a and b are constants).

What is a linear combination of matrices?

Linear combinations are obtained by multiplying matrices by scalars, and by adding them together. Therefore, in order to understand this lecture you need to be familiar with the concepts introduced in the lectures on Matrix addition and Multiplication of a matrix by a scalar. Definition. Linear combinations of vectors.