Question

What intervals would you use to determine where the function is positive and negative?

Answer 1

On edge

Explanation:

Answer 2

For this case we have a graph of a function
`y = f (x)` whose slope is given by:

`m =( f (x1) -f (x2))/( x2-x1)\\`

When
`m> 0` the graph is increasing

When
`m <0`the graph is decreasing

So:

• Interval (-∞, -1) slope
  `m> 0`, so the graph grows

• Interval [-1,2.5] the slope
  `m <0`, so the graph decreases

• Interval (2.5, ∞) slope
  `m> 0`, so the graph grows

Answer:

(-∞, -1)
`f (x)> 0\\`

[-1, 2.5]
`f (x) <0\\`

(2.5, ∞)
`f (x)> 0`