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Interval Notation- Uses inequalities to describe subsets of real numbers. Example: This is an example of a Bounded Interval That is because x is in the middle or bound by the numbers on the end We will use brackets and parenthesis to represent the numbers that x can be Since x can be equal to -2 we use a bracket: [ This means that x starts at -2 and can be equal to it Since x cannot be 6, we’ll use a parenthesis ) This means that x is less than 6 and cannot equal it Write an inequality to represent the following interval notation: Unbounded Interval Example: Write the following in interval notation: In this case the x is not in the middle of two numbers That means it’s not “bound” There are a infinite amount of numbers that are less than 6, so we’re going to have to use the infinity sign Since x is smaller than 6, the 6 is the right bound Use a bracket since it can be equal to The other side has an infinite number of solutions, so we’ll use the infinity sign Since it goes on forever in a negative direction, ∞ has to be negative Since you can’t equal infinity, use a parenthesis