Question

Please help. Look at screenshot

Answer 1

a. The function is increasing when
`x>4` and decreasing when
`x<4`.

b. The function is greater than zero when
`x<3` and
`x>5`

c. The function is less than zero when
`3<x<5`

Explanation:

a. The function
`f(x)` is increasing when it's instantaneous slope ( the slope of the line tangent to the graph ) is positive, and it is decreasing when the instantaneous slope is negative. We see from the graph of
`f(x)` that for
`x>4` the instantaneous slope is positive, and for
`x<4` the slope is negative.

b. From the graph we see that the function is greater the zero (has positive values ) when
`x<3` and
`x>5`.

c. The graph of the function is less than zero ( is negative) when
`3<x<5.`