In English we use the word combination loosely, without thinking if the order of things is important. In other words:

Find out how many different ways to choose items. For an in-depth explanation of the formulas please visit Combinations and Permutations.

Illustrated definition of Combination: Any of the ways we can combine things, when the order does not matter. Example: For a fruit salad, how many different...

Let us start with a function, in this case it is f (x) = x2, but it could be anything: f (x) = x2. Here are some simple things we can do to move...

The factorial function (symbol: !) says to multiply all whole numbers from our chosen number down to 1. Examples:

Undetermined Coefficients (that we learn here) which only works when f (x) is a polynomial, exponential, sine, cosine or a linear combination of those. Variation of Parameters which is a little messier but …

We can add, subtract, multiply and divide functions! The result is a new function. Let us try doing those operations on f (x) and g (x):

Illustrated definition of Factorial: Factorial says to multiply all whole numbers from the chosen number down to 1. The symbol is ! Examples:...

A System of Equations is when we have two or more linear equations working together.

☐ Understand that a function can be even, odd or neither even nor odd, and know how to determine whether a given function is even, odd or neither even nor odd.