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Answer :

Step-by-step explanation:

The function is decreasing when f(x) decreases as x increases.

We can observe one section that is increasing, it is when:

  • 0 ≤ x ≤ 3 (the black section)

So excluding this section, the decreasing sections are:

  • blue, red and green sections

or, when x is:

  • x ∈ (- ∞, 0) ∪ (3, + ∞)