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Select the correct answer. Consider these functions: $($)=3.13 + 2 g(t)=V Which statements, if any, are true about these functions? 1. The function fg(x)) = x for all real x. II. The function & x)) = x for all real x. III. Functions fand gare inverse functions. O A. I only B. ll only C.I, II, and III D. None of the statements are true.

User Ronak
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1 Answer

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\begin{gathered} f(x)=3x^3+2 \\ g(x)=\sqrt[3]{(x-2)/(3)} \end{gathered}

Let's verify every statement:

I.


f(g(x))=3(\sqrt[3]{(x-2)/(3)})^3+2=3((x-2)/(3))+2=x-2+2=x

So, the first one is true.

II:


g(f(x))=\sqrt[3]{((3x^3+2)-2)/(3)}=\sqrt[3]{x^3}=x

So, this one is true

III.

Since:


(fog)(x)=(gof)(x)=x

We can conclude that f(x) and g(x) are inverse functions. So, this statements is also true

Answer:

C.I, II, and III

User Dwich
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