### The Maxima on-line user's manual

Algebra Calculator

#### Del

Function: del (<x>) `del (<x>)` represents the differential of the variable x.

`diff` returns an expression containing `del` if an independent variable is not specified. In this case, the return value is the so-called "total differential".

Examples:

```          (%i1) diff (log (x));
del(x)
(%o1)                        ------
x
(%i2) diff (exp (x*y));
x y              x y
(%o2)            x %e    del(y) + y %e    del(x)
(%i3) diff (x*y*z);
(%o3)         x y del(z) + x z del(y) + y z del(x)```

There are also some inexact matches for `del`. Try `?? del` to see them.

```(%o1)                                true
(%i2) ```

### Related Examples

##### del-diff-eval

a1 = 1;

b1 = -2*((1/2)*((s - ...

c1 = ((1/2)*((s - x)^...

Calculate

L:400;

d:50;

D:60;

Calculate

##### del-ode2

ode2(del(y) = y*del(x...

Calculate

kill(all);

v1:1.0;

d:0.1;

Calculate

f: x*del(x);

Calculate

P:32;

A:481;

H:1.6*1000;

Calculate

##### del-integrate-sqrt

f: del(x)/(sqrt(1-x^2));

f1: integrate(f,x);

Calculate

del(x)*del(y);

Calculate

##### del-sqrt

xK: [8.64066, 9.83436...

yK: [6.1, 10.4, 13.3];

xK1: [12.8953, 13.64,...

Calculate

f: a*x*del(x);

Calculate