JEE Main 2021 — Functions Question with Solution
From: JEE Main 2021 (Online) 24th February Morning Shift
Question
Let f : R → R be defined as f (x) = 2x – 1 and g : R - {1} → R be defined as g(x) =
.
Then the composition function f(g(x)) is :
Choose an option
Show full solutionCorrect option: A
Correct answer
Aone-one but not onto
Step-by-step explanation
Given, f(x) = 2x 1; f : R R
Now, draw the graph of
Any horizontal line does not cut the graph at more than one points, so it is one-one and here, co-domain and range are not equal, so it is into.
Hence, the required function is one-one into.
Now, draw the graph of
Any horizontal line does not cut the graph at more than one points, so it is one-one and here, co-domain and range are not equal, so it is into.
Hence, the required function is one-one into.
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