JEE Mains · Maths · STD 12 - 1. relation and function
Let \(f, g: N -\{1\} \rightarrow N\) be functions defined by \(f(a)=\alpha\), where \(\alpha\) is the maximum of the powers of those primes \(p\) such that \(p^{\alpha}\) divides \(a\), and \(g(a)=a+1\), for all \(a \in N -\{1\}\). Then, the function \(f+ g\) is.
- A one-one but not onto
- B onto but not one-one
- C both one-one and onto
- D neither one-one nor onto
Answer & Solution
Correct Answer
(D) neither one-one nor onto
Step-by-step Solution
Detailed explanation
\(f: N-\{1\} \rightarrow N \quad f(a)=\alpha\) Where \(\alpha\) is max of powers of prime \(P\) such that \(p ^{\alpha}\) divides a. Also \(g ( a )= a +1\) \(f(2)=1\) \(g(2)=3\) \(f(3)=1\) \(g(3)=4\) \(f(4)=2\) \(g(4)=5\) \(f(5)=1\) \(g(5)=6\) \(f(2)+g(2)=4\) \((f(3)+g(3))=5\)…
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