JEE Mains · Maths · STD 12 - 1. relation and function
Let \(f:[0,3] \rightarrow\) A be defined by \(f(x)=2 x^3-15 x^2+36 x+7\) and \(g:[0, \infty) \rightarrow B\) be defined by \(\mathrm{g}(x)=\frac{x^{2025}}{x^{2025}+1}\). If both the functions are onto and \(\mathrm{S}=\{x \in \mathbf{Z}: x \in \mathrm{~A}\) or \(x \in \mathrm{~B}\}\), then \(\mathrm{n}(\mathrm{S})\) is equal to :
- A \(29\)
- B \(30\)
- C \(31\)
- D \(36\)
Answer & Solution
Correct Answer
(B) \(30\)
Step-by-step Solution
Detailed explanation
as \(f(x)\) is onto hence \(A\) is range of \(f(x)\)…
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