To combine radicals through addition or subtraction, they must have the same index and the same radicand (the expression under the radical). It is not always straightforward to determine if radicals can be combined because even if they have the same index, the radicands might seem similar but ultimately differ, leading to the inability to simplify them further.
What conditions must be met to combine radicals through addition or subtraction? Discuss why it is not always straightforward to determine if radicals can be combined in this manner. 1-2 sentences
5 answers
1-2 sentences
When multiplying radicals, you can directly multiply the radicands together and simplify the result if possible, following the rule \(\sqrt{a} \cdot \sqrt{b} = \sqrt{ab}\). In contrast, adding or subtracting radicals requires that the radicands be identical, as you can only combine them directly like terms when they share the same expression under the radical.
It is advantageous to divide the radicands before simplifying a fraction involving square roots when the radicands can be factored into simpler components, making it easier to simplify the overall expression. This approach is permitted by the property of radicals that states \(\sqrt{\frac{a}{b}} = \frac{\sqrt{a}}{\sqrt{b}}\), allowing separation of the numerator and denominator under the square root.