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Задача Задача №1366883
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Аноним
03 сентября 2024 13:13 · публичный вопрос
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Аноним

(5х-2)(х+6)>0

Нейросеть03 сентября 2024 13:13

To solve the inequality \( (5x - 2)(x + 6) > 0 \), we can follow these steps:

  1. Find the roots of the equation \( (5x - 2)(x + 6) = 0 \): \[ 5x - 2 = 0 \quad \Rightarrow \quad 5x = 2 \quad \Rightarrow \quad x = \frac{2}{5} \] \[ x + 6 = 0 \quad \Rightarrow \quad x = -6 \]

  2. Determine the critical points: The points where the expression is either zero or undefined are \( x = -6 \) and \( x = \frac{2}{5} \).

  3. Set up intervals based on the critical points: The critical points divide the number line into three intervals:

    • \( (-\infty, -6) \)
    • \( (-6, \frac{2}{5}) \)
    • \( (\frac{2}{5}, \infty) \)
  4. Test a point in each interval to determine where the inequality holds:

    • For the interval \( (-\infty, -6) \), choose \( x = -7 \): \[ (5(-7) - 2)(-7 + 6) = (-35 - 2)(-1) = (-37)(-1) = 37 > 0 \quad \text{(satisfies the inequality)} \]

    • For the interval \( (-6, \frac{2}{5}) \), choose \( x = 0 \): \[ (5(0) - 2)(0 + 6) = (-2)(6) = -12 < 0 \quad \text{(does not satisfy the inequality)} \]

    • For the interval \( (\frac{2}{5}, \infty) \), choose \( x = 1 \): \[ (5(1) - 2)(1 + 6) = (5 - 2)(7) = (3)(7) = 21 > 0 \quad \text{(satisfies the inequality)} \]

  5. Combine the results: The intervals where the product is greater than zero are \( (-\infty, -6) \) and \( (\frac{2}{5}, \infty) \).

  6. Write the solution: The solution to the inequality \( (5x - 2)(x + 6) > 0 \) is: \[ x \in (-\infty, -6) \cup \left( \frac{2}{5}, \infty \right) \]

So, the final answer is: \[ x < -6 \quad \text{or} \quad x > \frac{2}{5} \]

(5х-2)(х+6)>0
To solve the inequality \( (5x - 2)(x + 6) > 0 \), we can follow these steps: 1. **Find the roots of the equation \( (5x - 2)(x + 6) = 0 \)**: \[ 5x - 2 = 0 \quad \Rightarrow \quad 5x = 2 \quad \Rightarrow \quad x = \frac{2}{5} \] \[ x + 6 = 0 \quad \Rightarrow \quad x = -6 \] 2. **Determine the critical points**: The points where the expression is either zero or undefined are \( x = -6 \) and \( x = \frac{2}{5} \). 3. **Set up intervals based on the critical points**: The critical points divide the number line into three intervals: - \( (-\infty, -6) \) - \( (-6, \frac{2}{5}) \) - \( (\frac{2}{5}, \infty) \) 4. **Test a point in each interval to determine where the inequality holds**: - For the interval \( (-\infty, -6) \), choose \( x = -7 \): \[ (5(-7) - 2)(-7 + 6) = (-35 - 2)(-1) = (-37)(-1) = 37 > 0 \quad \text{(satisfies the inequality)} \] - For the interval \( (-6, \frac{2}{5}) \), choose \( x = 0 \): \[ (5(0) - 2)(0 + 6) = (-2)(6) = -12 < 0 \quad \text{(does not satisfy the inequality)} \] - For the interval \( (\frac{2}{5}, \infty) \), choose \( x = 1 \): \[ (5(1) - 2)(1 + 6) = (5 - 2)(7) = (3)(7) = 21 > 0 \quad \text{(satisfies the inequality)} \] 5. **Combine the results**: The intervals where the product is greater than zero are \( (-\infty, -6) \) and \( (\frac{2}{5}, \infty) \). 6. **Write the solution**: The solution to the inequality \( (5x - 2)(x + 6) > 0 \) is: \[ x \in (-\infty, -6) \cup \left( \frac{2}{5}, \infty \right) \] So, the final answer is: \[ x < -6 \quad \text{or} \quad x > \frac{2}{5} \]