Question

Which of the following represents the zeros of f(x) = x3 − 5x2 − 3x + 15?

5, square root of 3, −square root of 3
−5, −square root of 3, −square root of 3
5, −square root of 3, −square root of 3
−5, square root of 3, square root of 3

Answer 1

\[f(x) = x^3-5x^2-3x+15=0\]\[f(x) = x^2(x-5) +3(x-5) = 0\]\[f(x) = (x^2+3)(x-5)=0\]\[x^2+3=0 \qquad x=~?\]\[x-5=0 \qquad x=~?\]

Answer 2

X=-3
X=5

Answer 3

You've got one right

Answer 4

X^2=-3?

Answer 5

\[x^2+3=0 \implies x^2=-3\]\[x= \pm i\sqrt{3}\]Your answer choices are kind of weird.

Answer 6

so its A then right

Answer 7

Oh I think Im the one that made the mistake.

Answer 8

wait how

Answer 9

yes it's x^2 - 3

Answer 10

so it would still be A then right

Answer 11

ya

Answer 12

ok thank you

Answer 13

do you mind helping me with one more?

Answer 14

@Jhannybean
@ParthKohli

Answer 15

correction: \((x^2-3)(x-5)=0\)

Answer 16

It wouldnt let me post. -_-

Answer 17

i know that feel

Answer 18

Which of the following represents the zeros of f(x) = x3 − 14x2 + 61x − 84?

7, 4, −3
7, 4, 3
7, −4, −3
7, −4, 3

Answer 19

i believe it would be B

Answer 20

Look at the choices. We know that \(7\) is definitely a zero. Divide the thing by \(x - 7\). The remaining is a quadratic polynomial that can be factored.

Answer 21

or just plug in the choices lol idk who cares

Answer 22

Vieta's Formulas @Jhannybean :)

Answer 23

(x - 3) • (x - 4) • (x - 7)

Answer 24

i got this

Answer 25

so would it be B

Answer 26

=__=.... VF. How would that work here? we have one root = \((x-7)\)

Then we'd find \(\alpha +\beta \) and \(\alpha\beta\) ?

Answer 27

@ParthKohli darn it you logged.

Answer 28

@ganeshie8

Answer 29

srry i have to go

Answer 30

Np :)