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What is the value of f(-2) and f(3)

What is the value of f(-2) and f(3)-example-1
User Bryan Hong
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1 Answer

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23 votes

Answer:

Explanation:

When answering questions like this, we have to first decide which function we have to use. This is done by looking at the given domains (the x≤-2 etc). The first question ( f(-2) ), means we have to choose the function that applies to the x-coordinate -2. x=-2 is part of the section x ≤-2 since the sign means larger or equal to -2. Hence, we use the function 2x+8 to calculate f(-2). After finding this, the solving is relatively easy, just fill in the x-coordinate:

f(-2) = 2 * -2 + 8 = -4 + 8 = 4

The second one needs the same method. x=3 belongs in the section

-2 < x ≤ 3, since the final part means x is smaller or equal to 3, and in this case it is. Hence we use
x^(2) -3 here:

f(3) = 3² - 3 = 9 - 3 = 6

I hope this helps! Feel free to reach out if you still have questions

User Greg Ruhl
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