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Functions Videos 43 videos

Piecewise Functions
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Don’t even think about starting up your combo lemonade/fro-yo stand without first making sure you understand piecewise functions. You’re just a...

Introduction to Functions
17460 Views

This video will tell you all about the function of functions.

Function Rules, Tables, and Graphs
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Looking to find function formulas from tables? We've got all you need, right here in this video.

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SAT Math 2.3 Algebra and Functions 206 Views


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Description:

SAT Math 2.3 Algebra and Functions. Calculate this function.

Language:
English Language

Transcript

00:02

Here's your math-y shmoop du jour...

00:05

If f of x equals x squared minus x and g of x equals x minus 2,

00:11

what is g of f of negative 2?

00:16

And here are the potential answers...

00:20

So this problem just wants us to take two functions given,

00:23

and use them to find g of f of x.

00:25

As always, we start with the innermost set of parentheses.

00:30

We know that f of x equals x squared minus x.

00:35

Since we first want to find f of negative 2, we can replace x with negative 2.

00:41

If we do that, we get negative 2 squared minus negative 2 equals

00:47

4 minus negative 2, which equals 4 plus 2, which is 6.

00:51

f of negative 2 equals 6. Since we can replace f of negative 2 with

00:56

just plain old 6, the problem simplifies to g of 6.

01:01

G of x is equal to x minus 2, and in this case, x is f of negative 2, or 6.

01:10

So you just take 6 minus 2 to get 4, and... we've got our solution.

01:15

C's our guy.

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