ShmoopTube
Where Monty Python meets your 10th grade teacher.
Search Thousands of Shmoop Videos
Functions Videos 43 videos
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...
Looking to find function formulas from tables? We've got all you need, right here in this video.
SAT Math 2.3 Algebra and Functions 206 Views
Share It!
Description:
SAT Math 2.3 Algebra and Functions. Calculate this function.
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,
Full Transcript
- 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. What is the measure of angle z in terms of x and y?
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...
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...