If f(x) In and g(x) then find the value of
If f(x) = In x and g(x) = ex then find the value of f o g(2/3)?
- A.
2/3
- B.
1/3
- C.
4/3
- D.
None of these
Attempted by 352 students.
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Correct answer: A
Concept:
If g: A → B and f: B → C are functions then f o g (x) = f( g (x))
Calculation:
Given: f(x) = ln x and g(x) = eˣ
Here, we have to find the value of f o g(2/3)
⇒ f o g(2/3) = f( g(2/3))
∵ g(x) = eˣ so, g(2/3) = e²/³
⇒ f o g(2/3) = f(e²/³)
∵ f(x) = ln x, so f(e²/³) = ln (e²/³) = 2/3
Hence, f o g(2/3) = 2/3