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Question
Let f: R → R be given by f(x) = tan x. Then f–1(1) is ______.
Options
`pi/4`
`{"n" pi + pi/4 : "n" ∈ "Z"}`
Does not exist
None of these
Solution
Let f: R → R be given by f(x) = tan x. Then f–1(1) is `pi/4`.
Explanation:
Given that, f(x) = tan x
Let y = tan x
⇒ x = tan–1y
⇒ f–1(x) = tan–1x
⇒ f–1(1) = tan–11 = `pi/4`
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