ShmoopTube

Where Monty Python meets your 10th grade teacher.

Search Thousands of Shmoop Videos


Playlist Algebra and Functions Test Questions 74 videos

0
SAT Math 2.1 Algebra and Functions
272 Views

SAT Math 2.1 Algebra and Functions. What is g(h(4))?

1
SAT Math 2.3 Algebra and Functions
206 Views

SAT Math 2.3 Algebra and Functions. Calculate this function.

2
SAT Math 9.2 Algebra and Functions
377 Views

SAT Math 9.2 Algebra and Functions

See All

SAT Math 2.3 Algebra and Functions 206 Views


Share It!


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.

Related Videos

SAT Math 2.1 Geometry and Measurement
2779 Views

SAT Math 2.1 Geometry and Measurement. What is the measure of angle z in terms of x and y?

SAT Math 9.4 Algebra and Functions
1300 Views

SAT Math 9.4 Algebra and Functions

SAT Math 9.2 Algebra and Functions
377 Views

SAT Math 9.2 Algebra and Functions

SAT Math: Identifying an Equation for the Average of Two Percentages
23 Views

In 2014, the unemployment rate of one county in California was 7%. In another county, the unemployment rate was 11%. Which of the following express...

SAT Math: Which Equation Represents Profit?
13 Views

Angela is making cookies for a bake sale. She expects each batch of her cookies to sell for $40. It costs her $10 to make one batch of cookies, and...