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Introduction to Roots 4522 Views


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Description:

Get back to your roots with this video.

Language:
English Language

Transcript

00:04

Roots, a la Shmoop. In 1976, Alex Haley published a popular and

00:12

award-winning novel about race, emancipation and basic human rights...

00:16

Oh, so the book isn't what we're talking about right now?

00:22

Sorry, our bad. There we go.

00:26

Apparently, you're here to learn about an entirely different type of root.

00:32

Let's look at an example. Here's the square root of 9.

00:36

It's just the number 9 inside of a funny-looking symbol that resembles a checkmark.

00:41

Here's what this symbol is asking: "What number, when multiplied by itself, equals 9?"

00:50

Well, if you've ever drawn a Tic-Tac-Toe board, you should know that the answer is 3.

00:57

A root is really just the opposite of an exponent... ... 3 squared equals 9, and the square root

01:02

of 9 equals 3. Things get more complicated, however. Oh,

01:09

goody. Not every root is a square root. You can also

01:13

have a cubed root. Like this one: The 3 is telling you there is a number that

01:17

will fit this formula: You can plug in "2" to make this equation

01:23

complete, so we can say that 2 is the cube root of 8.

01:30

You can do the same with higher roots as well, although you are now entering serious headache

01:33

territory. If you don't feel like drawing the root symbol,

01:41

roots can also be expressed as exponents. If something is raised to the power of one-half,

01:50

it's the same as a square root. If it has an exponent of one-third, then we're

01:54

dealing with a cube root. Be careful, though, when negative numbers

01:58

enter the picture.

02:00

Those guys can mess you up. For example, there can never be a square root

02:08

of a negative, as multiplying any two numbers always gives you a positive result.

02:13

You CAN, however, have a cube root of a negative number.

02:18

We know there are a lot of rules to keep in mind... We hope this video wasn't too painful

02:23

for you... ...At least not as painful as a root canal.

02:27

Guess we'll stop drilling you...for now.

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