To determine whether the function \( y = 3\sqrt[3]{x} - 1 \) is increasing or decreasing, we should analyze its derivative.
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Find the derivative of the function: To find the derivative \( y' \): \[ y = 3\sqrt[3]{x} - 1 = 3x^{1/3} - 1 \] Applying the power rule, the derivative is: \[ y' = 3 \cdot \frac{1}{3} x^{-2/3} = x^{-2/3} \] Thus, \[ y' = \frac{1}{x^{2/3}} \]
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Analyze the sign of the derivative: The expression \( \frac{1}{x^{2/3}} \) is positive for all \( x > 0 \) (since \( x^{2/3} \) is positive).
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Conclusion: Since the derivative is positive for \( x > 0 \), the function is increasing on that interval.
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Final answer: The correct answer is option 1: increasing.