Question

Please help

the value -2 is lower bound for the zeros of the function below
f(x)=4x^3-12x^2-x+15
True or False

Answer 1

`\Large \boxed{\mathrm{False}}`

Explanation:

`\sf f(x)=4x^3-12x^2-x+15`

The zeros of the function is the values at which the function crosses the x-axis.

The value -2 is not a lower bound for the zeros of the function.

Answer 2

False

Explanation:

f(x)=4x^3-12x^2-x+15

Using synthetic division

-2 4 -12 -1 15

-8 40 -78

--------------------------

4 -20 39 -63

Since this is not zero, this is not a lower bound