Question

Find the zeros of the function.

f(x) = 4x3 - 12x2 - 40x

Answer 1

You need to factor to find where the function goes to zero.

Set f(x) = 0.
Start by factoring the greatest common factor from f(x).
Then try to rewrite your function as the product of binomials.

Answer 2

hint: greatest common factor is 4x

Answer 3

4x(x^2-3x-10) what now?

Answer 4

\[4x(x ^{2} - 3x - 10) = 0\]
divide the whole equation by 4x to remove 4x

Answer 5

\[
4x(x^2-3x-10) = 4x(x-5)(x+2) = 0 \\
x = -2, ~~x =0, ~~x=5 ~~\text{are the roots.}
\]

Answer 6

thanks! @aum

Answer 7

You are welcome.