Question 33: The function \(y = {x^3} – 3x\) has its minimum at x equals?

We have: \(y’ = 3{x^2} – 3 = 0 \Leftrightarrow \left[\begin{array}{l}x=1\\x=–1\end{array}\right\)[\begin{array}{l}x=1\x=–1\end{array}\right\)

Variation table:

Based on the variation table, the function has its minimum at x = 1.

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