COMEDK · Maths · 27. Application of Derivatives
\(f(x)=\left(\frac{5}{x}+7\right)\), where \(x \neq 0\) is decreasing for
- A \(x \in R\)
- B \(x \in R-\{0\}\)
- C \(x \in R-\{1\}\)
- D \(x \in R-\{-1,1\}\)
Answer & Solution
Correct Answer
(B) \(x \in R-\{0\}\)
Step-by-step Solution
Detailed explanation
\(f(x)=\left(\frac{5}{x}+7\right)\) \(\Rightarrow f^{\prime}(x)=\frac{-5}{x^{2}} < 0\) for all \(x \in R\), where \(x \neq 0\). Hence, \(f(x)\) is decreasing for \(x \in R-\{0\}\).
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