# Math --- **Math** is a subject about numbers and such. It is important to have a good foundation in math for [[nursing]]. - [[Statistics]] is a branch of math that has to do with making the most sense possible out of large number sets. - [[Algebra]] is a branch of math that has to do with *balance*. - [[Trigonometry]] is a branch of math that explores triangles, circles, and degrees. ## Types of Numbers What are numbers? This is actually a really difficult, almost existential question so let's just intuit what numbers are and go from there. An **integer** is a whole number—either positive or negative—or zero. This is opposed to a [[fractions]], decimals or imaginary numbers. **Rational numbers** are numbers that are either finite (i.e. 10, 234.7) or repeat forever, (i.e. 6.333̅, or 3.6̅7̅). Rational numbers can always be expressed as [[fractions]] (where both numerator and denominator are integers and the denominator *is not equal to* 0), such as $\frac{3}{4}$. **Irrational numbers** are numbers that are infinite and non-repeating. For example, **π** is irrational because it just goes on forever and doesn't repeat itself for long enough to count. √7 is irrational because 7 is not a perfect square (but √25 is because 25 is a perfect square). ## Order of Operations The **order of operations** is like the grammar of math. It is a standardized order in which to perform mathematical operations in equations where there is more than one. The acronym for it is **PEMDAS**, or **P**arenthesis, **E**xponents, **M**ultiplication/**D**ivision, **A**ddition/**S**ubtraction. ## Fractions A [[fractions|fraction]] is a way of representing a part of a whole number. ## Dimensional Analysis [[Dimensional analysis]] is a tool you can use to determine an equivalent value of something given in one unit, in another unit. For example, you can determine how many seconds are in a year, if you know how many seconds are in a minute, how many minutes are in an hour, how many hours are in a day and how many days are in a year. ___