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[Function Composition] could someone help me with this answers or show work either is fine

[Function Composition] could someone help me with this answers or show work either-example-1
User Asanka
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1 Answer

5 votes

Answer:

21

Explanation:

Given the following expressions

f(x) = x³-2x

g(x) =-x-2

We are to find (fog)(-5)

fog = f(g(x))

f(g(x)) = f(-x-2)

Replace x with -x-2 in f(x)

f(-x-2) = (-x-2)³-2(-x-2)

f(-x-2) = (-x-2)³+2x+4

fog = (-x-2)³+2x+4

Substitute x = -5 into the result

fog(-5) = (-x-2)³+2x+4

fog(-5) = (-(-5)-2)³+2(-5)+4

fog(-5) = (5-2)³-10+4

fog(-5) = 3³-6

fog(-5) = 27-6

fog(-5) = 21

Hence the required result of the composite function is 21

User Mustex
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