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SAT Math 1.1 Statistics and Probability. In which of the following data sets are the arithmetic mean and the median equal?
SAT Math: Statistics and Probability Drill 1, Problem 2. If the four largest numbers in the set were doubled, what would happen to the median...
SAT Math 1.3 Statistics and Probability. Approximately what is the probability that they will be placed in alphabetical order?
SAT Math 2.3 Algebra and Functions 211 Views
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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.
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