iran-konkur 2021 Q122

iran-konkur · Other · konkur-riazi_1400_specialized 3 marks Stationary points and optimisation Determine intervals of increase/decrease or monotonicity conditions
122. For the function $f(x) = 2\sqrt{x} - \dfrac{3}{2\sqrt[3]{x^2}-1}$, which statement is correct?
(1) $f$ is increasing on $(1,\infty) \cup (0,1)$.
(2) $f$ is increasing on $(1,\infty)$ and $(0,1)$.
(3) $f$ is increasing on $(1,\infty)$ and decreasing on $(0,1)$.
(4) $f$ is decreasing on $(1,\infty)$ and increasing on $(0,1)$.
\textbf{122.} For the function $f(x) = 2\sqrt{x} - \dfrac{3}{2\sqrt[3]{x^2}-1}$, which statement is correct?

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(1) $f$ is increasing on $(1,\infty) \cup (0,1)$.

(2) $f$ is increasing on $(1,\infty)$ and $(0,1)$.

(3) $f$ is increasing on $(1,\infty)$ and decreasing on $(0,1)$.

(4) $f$ is decreasing on $(1,\infty)$ and increasing on $(0,1)$.

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