GeoGebra
GeoGebra has built-in tools for computing factorials, permutations and combinations, just like your calculator.
GeoGebra Instruction 1
Open CAS under 
View in 
Menu.
-
To compute a factorial, type your number immediately followed by “!” and press
Enter. -
To compute permutations, type
nPr. Select the commandnPr(<n>, <r>). Enter the total number of elements, and then the number of elements to be drawn from the total. PressEnter. -
To compute combinations, type
nCr. Select the commandnCr(<Number n>, <Number r>). Enter the total number of elements, and then the number of elements to be drawn from the total. PressEnter.
