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The two functions f and g are inverse functions if and only if both of their compositions are the identity function.
Yes
We want to determine whether the given pair of functions are inverse functions. f(x)=2x+16 and g(x)= 12x-8 To do so, we need to verify that the compositions of f(x) and g(x) are the identity function.
Recall that [f ∘ g](x) = f(g(x)). To find the expression, we will start by substituting 12x-8 for g(x).
Now we apply the definition of f(x). f(x)=2x+16 ⇓ f( 12x-8 ) = 2( 12x-8 ) + 16 Finally, let's simplify and see if the function is the identity function.
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Add terms
We found that [f ∘ g](x) is the identity function.
Similarly, recall that [g ∘ f](x) = g( f(x) ). To find the expression, this time we will start by substituting 2x+16 for f(x).
Now we apply the definition of g(x). g(x)= 12x-8 ⇓ g( 2x+16 ) = 12( 2x+16)-8 Finally, let's simplify and see if the function is the identity function.
Distribute 12
Subtract terms
We found that [g ∘ f](x) is also the identity function. As such, f(x) and g(x) are inverse functions.