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If f(x) = 5x2 − 4 and g(x) = x − 2, what is (f o g)(-3)?

User HannahMitt
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2 Answers

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Final answer:

To calculate (f o g)(-3), first evaluate g(-3) which is -5. Next, plug this into f(x) to get f(-5), yielding a result of 121. Thus, the value of (f o g)(-3) is 121.

Step-by-step explanation:

The student is asking to calculate the composition of two functions, specifically (f o g)(-3), where f(x) = 5x² − 4 and g(x) = x − 2. The composition (f o g)(x) means we first apply g to x, and then apply f to the result of g(x).

Step 1: Evaluate g(-3), which gives -3 − 2 = -5.

Step 2: Substitute the g(-3) value into f, to get f(-5), which is 5(-5)² − 4.

Step 3: Calculate f(-5). Since (-5)² is 25, and 5×25 is 125, we have 5(-5)² − 4 equals 125 − 4, which is 121.

Therefore, the value of (f o g)(-3) is 121.

User Hlh
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1 vote
F of g is
5(-3)2-4
(-15)2-4
-30-4
-34
G(x)= -3-2
G(x)=-5
User Reshetech
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8.0k points