A function is used in an expression to call a predetermined operation to be performed in an operand They must be used in conjunction with either a statement or a command Examples are shown in table below
| Functions | Meaning |
|---|---|
| SIN (x) | The sign of x |
| Cos (x + y) | The cosine of the addition of x and y |
| TAN (x – y) | The tangent of subtraction of y from x |
| ATN (x) | Arctangent of x |
| EXP (x) | The exponential value of x |
| LOG (x) | The natural logarithm of x |
| SQR (x) | The square root of x |
| ABS (x) | The absolute value of x |
| SPC (x) | Leave x space |
| TAB (x) | Start at position x + 1 |
| SGN (x) | The sign of x; 1 if x > 0, 0 if x = 0, -1 if x < 0 |
Note: The quantity x is called the argument or parameter