# Mathematical operations in Octave

In this lesson, I'll explain what are the operators that allow you to perform the main mathematical operations on Octave.

**Addition**

The addition operator is +

>> 3+2

ans = 5

**Subtraction**

The subtraction operator is -

>> 3-2

ans = 1

**Multiplication**

Multiplication multiplication operator is

>> 4*2

ans = 8**c**

**Division**

The division operator is /

>> 8/2

ans = 4

**Remainder of the Division**

To calculate the remainder of the division use the mod() function

>> mod(7,2)

ans = 1

**Warning**. Unlike many programming languages, the Octave software does not use the percent symbol % to calculate the remainder of division, because the % symbol is used to write comments. So if you write 7%2 the software treats 2 as a comment and returns 7 as the result. Therefore, if you need to calculate the modulus of division you must use the mod() function.

**Power**

The power operator is ^

>> 2^3

ans = 8

Alternatively, you can also use the double asterisk to calculate the exponentiation of a number

>> 2**3

ans = 8

**Square root
**

To calculate the square root you have to use the function sqrt()

>> sqrt(16)

ans = 4

Alternatively you can raise the number by the fraction 1/2

>> 16**(1/2)

ans = 4

In addition to these basic math operators, there are many other Octave functions that allow you to perform many other math operations

**abs(x)**

returns the absolute value of x**cos(x)**

calculate the cosine of x**sin(x)**

calculate the sine of x**tan(x)**

calculate the tangent of x**acos(x)**

calculates the arc cosine of x**asin(x)**

calculate the arcsine of x**atan(x)**

compute the arc tangent x**exp(x)**

calculate the exponential of x**log(x)**

calculate the natural logarithm of**log10(x)**

calculate the base 10 logarithm of x**sqrt(x)**

calculate the square root of x**nthroot(x,n)**

calculate the nth real root of x

For example to calculate the absolute value you can use the abs() function

>> abs(-1)

ans = 1

In general, Octave results are displayed in short format with 5 significant digits by default.

However, you can change the number format (long/short) or use scientific notation.