Like Radicals
See It in Action
Two examples of the idea done right—and one common look-alike that is not right.
EXAMPLE
EXAMPLE
NON-EXAMPLE
Definition
Like radicals are terms that have the same radicand (the number or expression inside the radical) and the same index (the type of root being taken, such as square root, cube root, etc.).
For example:
3sqrt(5) and 2sqrt(5) are like radicals because both have the same radicand 5 and both are square roots (same index).
4 cube rt(7) and 6cube rt(7) are like radicals because both have the same radicand 7 and both are cube roots (same index).
Unlike radicals, on the other hand, would be terms with different radicands or different indices. For example, 2sqrt(3) and 3sqrt(5) are not like radicals because the radicands are different (3 vs. 5).
You can add or subtract like radicals just like like terms in algebra. For instance:
But you cannot directly add or subtract unlike radicals.