Principle objective of this lecture is to present on Foiling Radicals. Here briefly focus on how to multiply Radical Expressions with the FOIL Method and how do we Multiply Radical Expressions. A radicand is the term under the square root. We multiply radicals by multiplying their radicands together while keeping their product under the same radical symbol. In this tutorial, we are only going to deal with square root, a specific type of radical expression with an index of 2.