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If (f + g)(x) = 3x2 + 2x – 1 and g(x) = 2x – 2, what is f(x)?

3x2 + 1
3x2 – 1
3x2 + 4
3x2 – 4
x2 – 2

User Mishimay
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1 Answer

3 votes
To find f(x) we subtract g(x) from (f+g)(x):

3 x^(2) +2x-1-(2x-2) \\ 3 x^(2) +2x-1-2x+2 \\ 3 x^(2) +1 Distribute the negative across the parentheses and then combine like terms. The 2x gets cancelled out and we are left with
A. 3 x^(2) +1

Hope that helps.
User Asontu
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