# Math

Using numbers, number operators, and math functions.

## Numeric values: 0, 1, 2, 6.7, 10.083…

Just numbers by themselves. Sometimes these are called *numeric literals*.

### Integers: whole numbers

```
let num = 0;
num = 0;
num = 1;
num = 2;
```

### Floating point: numbers with a fractional part

Numbers can have their fractional part too. The decimal point is between the digits of the number.
But, *floating point* numbers have the decimal point at any spot between digits, like: 3.14159 or 651.75.

```
let num = 0
num = 6.7
num = 10.083
```

### Arithmetic binary operation (+, -, *, /)

The operations for basic arithmetic: add, subtract, multiply, and divide.

```
let more = 0+1;
let less = 0-1;
let twice = 1*2;
let divide = 8/4;
```

### Remainder (%)

This is a extra operator for division. You can find out how much is left over if one number doesn’t divide into the other number evenly.

We know that 4 / 2 = 2, so 2 divides into 4 evenly. But, 5 / 2 = 2 with a remainder of 1. So, the remainder operation, 5 % 2 = 1, gives the number that’s left over from a division operation.

`let remainder = 7%4;`

### Exponent (**)

The exponent operator will multiply the number on the left by itself for the amount of times of the number on its right. That is, 4 ** 2 = 4 * 4 and 2 ** 3 = 2 * 2 * 2. The area of a square that has sides with a length of `5`

is equal to one side multiplied by another. For a square, all sides are equal, so:

```
let side = 5;
let area = side * side;
```

But using the exponent operator, this is the same as:

```
let side = 5;
let area = side ** 2;
```

The volume of a cube is three sides multiplied together. The two volumes are the same:

```
let side = 5;
let volume1 = side * side * side;
let volume2 = side ** 3;
```

## Square root

The square root of a number is another number that when multiplied by itself it becomes the original number. You know that `2 * 2`

equals `4`

so the square root of `4`

is `2`

. It’s called a *square root* because the area of a *square* is the length of two equal sides multiplied together. The *root* is the length of a side.

```
let side = 5
let square = side * side
let root = Math.sqrt(side)
```

## Absolute value

When you want to know how much a number is without its *sign* (+/-). The absolute value of -5 is 5 and the absolute value of 5 is also 5. The absolute value is sometimes called the *magnitude*.

`let item = Math.abs(-5);`

## Minimum and maximum of two values

You can get the smaller or the bigger of two numbers with the min and max functions.

- The minimum of 2 and 9:
**Math.min(2, 9)**equals 2. - The maximum of 3 and 9:
**Math.max(3, 9)**equals 9.

```
let minval = Math.min(0, 1);
let maxval = Math.max(8, 2);
```

## Random value

Make up any number from a minimum value to a some maximum value. If you want a random number up to
100, say: **Math.randomRange(0, 100)**.

`let myRandom = Math.randomRange(0, 5);`

## See also

abs, min, max, randomRange