Find the interval in which the following functions are strictly increasing or decreasing.
`-2x^(3) - 9x^(2) - 12x + 1`

Find the interval in which the following functions are strictly increasing or decreasing. (d) 6 - 9x - x^(2)

Find the intervals in which the following functions are strictly increasing or decreasing: -2x^3 - 9x^2 - 12x +1

Find the invervals in which the following functions are strictly increasing or decreasing : -2x^(3)-9x^(2)-12x+1

Find the intervals in which the following functions are strictly increasing or decreasing: 6-9x-x^2

Find the intervals in which the following functions are strictly increasing or decreasing : f(x)=2x^(3)-9x^(2)-12x+15

Find the intervals in which the following functions is increasing or decreasing. f(x) = - 2x^(3) - 9x^(2) - 12x + 1

Find the intervals in which the following functions are strictly increasing or strictly decreasing. 6 - 9x - x^(2)

Find the intervals in which the following functions are strictly increasing or strictly decreasing. x^(3) + 3x^(2) - 6x + 12