Cubing a number is one thing - uncubing a number is something else entirely. Uncube numbers with help from a mathematics educator in this free video clip.

Save

Cubing a number is one thing - uncubing a number is something else entirely. Uncube numbers with help from a mathematics educator in this free video clip.

Part of the Video Series: Mathematics Lessons

Promoted By Zergnet

Hi. I'm Jimmy Chang and we're here to talk about how to uncube numbers. Now, most folks don't really talk about uncubing numbers, rather they talk about the operation that's opposite cubing which is taking the cube root of a number. So, the notation associated with cube-rooting is oftentimes the radical with the three inside the little hook here. Now, it really depends by the number and when it comes to finding the cube root of a value, because every number's going to be different. Now, when it comes to taking square roots we talk about perfect squares. When we talk about taking cube roots we're referring to perfect cubes. Not a lot of perfect cubes out there but some are more workable than others. So for example, suppose you have cube root of eight. What you gotta think about is what number, multiplied by itself three times is going to give you eight? The only number that really comes to mind is the number two because two to the third is going to give you eight. So, that's another way to think about it. Here's another illustration. Suppose you want to find out the cube root of negative twenty-seven. You gotta think about what number multiplied by itself, or, raised to the third power is going to give you negative twenty-seven. Now, because it's a negative number in here and we're talking about cube rooting, you may think it's going to be a negative number and you would be right. As a matter of fact, the only number that fits that description is negative three because negative three raised to the third is going to give you negative twenty-seven. Now, is every number going to work out like this? Unfortunately not. For example, if you have a cube root of twelve it's a lot more difficult to manage because there's no number multiplied by itself three times or raised to the third that's going to give you twelve. So when it comes to cube rooting a number some numbers will work, while some numbers you may just have to either simplify very little or just leave it inside the radical all together. So, I'm Jimmy Chang and that's how you would quote unquote uncube a number.