The Large page on the Equations panel contains sums, products, integrals, intersections, and unions.
If an expression is selected when you insert a large element, the expression becomes the first operand. The following examples show the result of clicking the summation symbol 
on the Large page.
|
Before clicking |
After clicking |
|---|---|
|
|
|
|
|
|
You can add an operand after inserting a math element from the Large page.