iran-konkur 2022 Q123

iran-konkur · Other · konkur-riazi_1401_specialized Stationary points and optimisation Determine parameters from given extremum conditions
123-- Point $A(-1,1)$ is a relative extremum of the function $y=x^{2}|x|+3ax^{2}+b$. The value of $\dfrac{b}{a}$ is which of the following?
(1) $-3$ (2) $-\dfrac{1}{3}$ (3) $3$ (4) $\dfrac{1}{3}$
\textbf{123--} Point $A(-1,1)$ is a relative extremum of the function $y=x^{2}|x|+3ax^{2}+b$. The value of $\dfrac{b}{a}$ is which of the following?

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(1) $-3$ \hfill (2) $-\dfrac{1}{3}$ \hfill (3) $3$ \hfill (4) $\dfrac{1}{3}$

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