Mathematics · 2025
JEE Main · 22 January 2025, Shift 2 · Q1
Let A ={1,2,3,4} and B ={1,4,9,16}. Then the number of many-one functions f: A → B such that 1 ∈ f( A ) is equal to:
Let $\displaystyle \mathrm{A}=\{1,2,3,4\}$ and $\displaystyle \mathrm{B}=\{1,4,9,16\}$. Then the number of many-one functions $\displaystyle f: \mathrm{A} \rightarrow \mathrm{B}$ such that $\displaystyle 1 \in f(\mathrm{~A})$ is equal to :
Official answer
From NTA’s final answer key for this paper.
(2)
$\displaystyle 151$
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JEE Main 2025 Mathematics question, with the answer from NTA’s final answer key. Where our answers come from.