Mathematical Notation in Notebooks
If you use the notebook front end for Mathematica, then you can enter some of the operations discussed here in special ways.
 | Sum[f,{i,imin,imax}] | sum |
 | Product[f,{i,imin,imax}] | product |
 | Integrate[f,x] | indefinite integral |
 | Integrate[f,{x,xmin,xmax}] | definite integral |
 | D[f,x] | partial derivative |
 | D[f,x,y] | multivariate partial derivative |
Special and ordinary ways to enter mathematical operations in notebooks.
This one of the standard palettes for entering mathematical operations. When you click a button in the palette, the form shown in the button is inserted into your notebook, with the black square replaced by whatever you had selected in the notebook.
| EscsumEsc | summation sign  |
| EscprodEsc | product sign  |
| EscintEsc | integral sign  |
| EscddEsc | special differential for use in integrals |
| EscpdEsc | partial derivative  |
| Ctrl+_ or Ctrl+- | move to the subscript position or lower limit of an integral |
| Ctrl+^ or Ctrl+6 | move to the superscript position or upper limit of an integral |
| Ctrl++ or Ctrl+= | move to the underscript position or lower limit of a sum or product |
| Ctrl+& or Ctrl+7 | move to the overscript position or upper limit of a sum or product |
| Ctrl+% or Ctrl+5 | switch between upper and lower positions |
| Ctrl+Space | return from upper or lower positions |
Ways to enter special notations on a standard English-language keyboard.
You can enter an integral like this. Be sure to use the special differential

entered as
EscddEsc, not just an ordinary

.
| Out[1]= |  |
Here is the actual key sequence you type to get the input.
| Out[2]= |  |
When entering a sum, product or integral that has limits, you can create the first limit using the standard control sequences for subscripts, superscripts, underscripts, or overscripts. However, you must use Ctrl+% to create the second limit.
You can enter a sum like this.
| Out[3]= |  |
Here is the actual key sequence you type to get the input.
| Out[4]= |  |