JEE Main 202227 JulyMorning Shift
- Exam
- JEE Main
- Year
- 2022
- Date
- 27 July
- Shift
- Morning Shift
- Subject
- Mathematics
- Chapter
- Functions
JEE Main 2022 · 27 July · Morning Shift · Mathematics · Functions
Let f, g: ℕ - \ 1\ → ℕ be functions defined by f(a) = α , where α...
Let be functions defined by , where is the maximum of the powers of those primes such that divides , and , for all . Then, the function is
Options
- Aone-one but not onto
- Bonto but not one-one
- Cboth one-one and onto
- Dneither one-one nor onto
Correct answer
D. neither one-one nor onto
Step-by-step solution
Given,
defined as
, where is the maximum power of those primes such that divides a.
Now,
We can see \left(f + g\right)\left(5\right) = \left(f + g\right)\left(4\right)f + g{f}_\min = 1, {g}_\min = 3x \in N - \left\{1\right\} such that \left(f + g\right)\left(x\right) = 1, 2, 3∴ f + g is not onto
So function is neither one-one nor onto.