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Given the definitions of f(x) and g(x) below, find the value of (fog)(-2).
f(x) = 3x2 + 6x +11

User Grinch
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1 Answer

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Final answer:

To find the value of (fog)(-2), substitute -2 into the function g(x) and then substitute the result into the function f(x).

Step-by-step explanation:

To find the value of (fog)(-2), we need to substitute -2 into the function g(x) and then substitute the result into the function f(x).

Given that f(x) = 3x^2 + 6x + 11, let's first find g(-2):

g(x) = -13 ± √((13)^2 - 4 × 3 × (-10))

g(x) = -13 ± √(169 + 120)

g(x) = -13 ± √(289)

g(x) = -13 ± 17

Therefore, g(-2) = -13 + 17 = 4

Now, substitute g(-2) into f(x):

f(g(-2)) = 3(4)^2 + 6(4) + 11

f(g(-2)) = 3(16) + 24 + 11

f(g(-2)) = 48 + 24 + 11

f(g(-2)) = 83 + 11

f(g(-2)) = 94

User Kevin Newman
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