Answers in bold
- Increasing on the interval (-2.5, 0)
- Decreasing on the interval (-∞, -2.5) U (0, ∞)
Each answer is in interval notation.
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Explanation:
The graph is increasing when the curve goes uphill when moving to the right.
This occurs on the interval -2.5 < x < 0 which condenses to the interval notation (-2.5, 0); be sure not to mix this up with ordered pair notation which unfortunately looks identical.
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The graph is decreasing when the curve goes downhill when moving to the right.
This happens on two separate intervals of -∞ < x < -2.5 and 0 < x < ∞ which condense to the interval notation (-∞, -2.5) and (0, ∞) respectively.
Joining those two intervals up with the union symbol gets us
(-∞, -2.5) U (0, ∞)
