Identify two key differences between the procedures for multiplying radicals and the procedures for adding or subtracting them.

1 answer

Here are two key differences between the procedures for multiplying radicals and for adding or subtracting them:

  1. Combining Terms vs. Multiplying Terms:

    • Adding/Subtracting Radicals: When adding or subtracting radicals, the terms must be like radicals (i.e., they must have the same radicand). For example, \(\sqrt{2} + 3\sqrt{2} = 4\sqrt{2}\), while \(\sqrt{2} + \sqrt{3}\) cannot be simplified further because the radicands are different.
    • Multiplying Radicals: When multiplying radicals, you can multiply them regardless of whether the radicands are the same. For instance, \(\sqrt{2} \times \sqrt{3} = \sqrt{6}\).
  2. Simplifying Outcomes:

    • Adding/Subtracting Radicals: The focus is primarily on finding common terms (like terms) and simplifying the expression as much as possible based on those common terms.
    • Multiplying Radicals: The process often involves applying the property \(\sqrt{a} \times \sqrt{b} = \sqrt{ab}\), and simplification often involves factoring the radicand to pull out any perfect squares. For example, \(\sqrt{8} = \sqrt{4 \times 2} = 2\sqrt{2}\).

In summary, adding and subtracting radicals requires like terms, while multiplying does not, and the simplification processes differ significantly as well.