Subtracting surds
We can only subtract surds that have the same surd part (the part under the root).
When subtracting surds with the same surd part, we simply subtract the coefficients (the numbers in front of the surd).
Example: simplify 6\sqrt{5}-4\sqrt{5}
=(6-4)\sqrt{5} =2\sqrt{5}
Example: simplify 9\sqrt{7}-3\sqrt{7}
=(9-3)\sqrt{7} =6\sqrt{7}
flashcards
| Question | Answer |
|---|---|
| When subtracting surds, when can we directly subtract them? | We can only subtract surds that have the same surd part (the part under the root). |
| How do we subtract surds that have the same surd part? | We simply subtract the coefficients (the numbers in front of the surd). |
| Simplify | |
| Simplify |