» **diff **

If the 'order' is omitted, the first order derivative is assumed.

The function is used to perform symbolic or numeric derivatives. It can be inserted by typing

Chose the

We could have defined the 'expression'

and found the first derivatives over the variables (partial derivatives, actually):

How to obtain the higher order derivatives? Press comma after the 'variable' and in the obtained placeholder insert the 'order' (integer). Here are the second derivatives:

Here are mixed derivatives as well:

Instead of an expression we could have defined a function and repeat the procedure:

Numerical derivatives are found at the given values. For instance:

Very important SMath feature is ability to find the