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16 votes
Find (g•f)(3)
f(x) = |x + 2|
g(x)=-x^2

1 Answer

5 votes

Answer:

-25

Explanation:

This question is asking for a composite function.

Let's take this step-by-step!


f(x) = |x + 2|\\g(x) = -x^2

(g•f)(3) means
g(f(3))

In English, this means we put 3 into f(x), and use the result for g(x).

First let's do f(x):


f(3) = |3 + 2| = |5| = 5

The lines mean "modulus"/"absolute value" which makes any number positive

For example,


|-3| = 3


f(3) = 5\\g(f(3)) = g(5)\\g(5) = -(5)^2 = -25

User Wolfcastle
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