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If f(x)= 3x +2 and g(x)=x^2+1, which expression is expression is equivalent to (fog) (x)

User Shankze
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1 Answer

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Composite Functions

Composite functions occur when we take two functions and input one into the other as x.

Example:


f(x) = 2x


g(x) = 3x^2


(f\circ g)(x)=f(g(x))


(f\circ g)(x) = 2(3x^2)

Solving the Question

We're given:


  • f(x)= 3x +2

  • g(x)=x^2+1

To find
(f\circ g)(x), input g into f as x:


f(x)= 3x +2


(f\circ g)(x)=3(x^2+1) +2\\(f\circ g)(x)=3x^2+3 +2\\(f\circ g)(x)=3x^2+5

Answer


(f\circ g)(x)=3x^2+5

User Chawkins
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