# The partial derivative symbol with subscript - what does it mean and how do I type it?

The guide that I am using to study Mathematica tells me to type the following

to get

I am stuck at the partial derivative symbol because I do not understand what it exactly means with the subscripted parenthesis, nor do I know how to type it in. Thanks in advance for helping!

• About how to type it: go to Palletes -> Writing Assistant and there you'll find that the partial derivative can be typed with esc+pd+esc. With an input form, you can highlight the cell and use ctrl+shift+n to convert it to a standard form. About what does a partial derivative mean, that's a mathematical question - see, e.g., here. – corey979 Oct 25 '16 at 19:52
• I tend to recommend against using the Palletes. Just type the code in, i.e. Table[D[y[x], {x, i}] /. x -> 0, {i, 1, 4}]. – march Oct 25 '16 at 19:54

In Mathematica, $\partial_{b, c, \dots} a$ is completely equivalent to D[a, b, c, ...]. It's just a different notation. What follows the $\partial$ sign is the first argument of D. The subscript is the rest of the arguments.

See D for how to use D.

Type the $\partial$ notation using

esc pd esc ctrl-_

Personally I prefer to stick to the D[...] notation.

The partial derivative symbol tells you the following: In the subscript you can see two letters. The first one tells you according to what you are differentiating, in your case "x". The second one,"i" tells you the order of differentiation, so how many times you are differentiating.

As march said in his comment, the equivalent Mathematica code is: Table[D[y[x], {x, i}] /. x -> 0, {i, 1, 4}]

• @ corey979 Thanks ! :) – henry Oct 26 '16 at 13:16