Click change to change anything, and solve to solve it. To use i, just type i when making the problem. For all the rules on using the Shunting Yard Algorithm, look at my project for it. An example is factorials where the bottom is 1, the top number is the number you want the factorial of, and the problem on the right is i.
The surprisingly understandable wikipedia part for this: http://en.wikipedia.org/wiki/Multiplication#Capital_Pi_notation Note: All of the numbers that are not being used in problem have to be numbers, no variables.
