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Which of these pairs of functions are inverse functions
please help :(

Which of these pairs of functions are inverse functions please help :(-example-1
User Unbalanced
by
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1 Answer

3 votes

Answer:

see below (both 2nd and 3rd choices)

Explanation:

One way to tell if the functions are inverses is to look at f(g(x)). If the functions are inverses, then f(g(x)) = x.

A: f(g(x)) = 2^((log2(x -1) -1) -1) +1 = (2^(log2(x-1))(2^-2) +1 = (1/4)(x -1) +1 ≠ x

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B: f(g(x)) = (1/2)(ln((2e^(2x+1))/2) -1) = (1/2)(ln(e^(2x+1)) -1) = (1/2)(2x +1 -1) = x

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C: f(g(x)) = 4ln(e^((e^2x/8))^2)/e^2 = 8(e^2x/8)/e^2 = x

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D: f(g(x)) = 10^((log(x+10)-10) -10)-10 = (10^log(x+10))(10^-10) -10

= (x +10)(10^-10) -10 ≠ x

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The 2nd and 3rd pairs of functions listed are inverses of each other.

Which of these pairs of functions are inverse functions please help :(-example-1
User Mithun
by
4.9k points