Question

If x = 1 is a zero of the polynomial function f(x) = 3x3 − 8x2 + 3x + 2, which of the following is another zero of f(x)?
MEDAL AND FAN PLEASE

Answer 1

@welshfella @WazapxD @Michele_Laino

Answer 2

wouldnt be a x behind 2

Answer 3

4x^3-8x^2+3x+2

Answer 4

ima work this out brb

Answer 5

ok

Answer 6

whats the answer choices

Answer 7

(x-2) (3x+1) (x-1) are the factors of the polynomial function

Answer 8

sets of zeroes are x=2 x= -1/3 x=1

Answer 9

The answer choices are 2, -2, -1, 5

Answer 10

it is 2

Answer 11

how?

Answer 12

you need to factor the trinomial function to find the zeroes

Answer 13

but wouldn't it be -1,2, and 1/3

Answer 14

yes that is correct
they're 3 zeroes in a cube root unless one of the zeroes is repeated

Answer 15

they are only looking for another one

Answer 16

which is 2 or -1/3 since 1 is given

Answer 17

ok. can i ask another?

Answer 18

yes

Answer 19

Anyone?

Answer 20

this is the Descartes rule of signs which i've only got a vague memory of . I'll see if I can find a website for you. Or maybe someone who remembers it will come along..

Answer 21

http://openstudy.com/study#/updates/50193b0ee4b04dfc808cb938

Answer 22

Here is a link to a similar question

Answer 23

But I still don't understand it :(

Answer 24

http://www.purplemath.com/modules/drofsign.htm

Answer 25

:) Thank you!!

Answer 26

Which polynomial identity will prove that (3 + 6)2 = 81?

Answer 27

power rule

Answer 28

there are 3 changes of sign in this polymomial

Answer 29

so would it be difference of squares?

Answer 30

Square of a Binomial

Answer 31

Which of the following is a polynomial with roots: −square root of 3, square root of 3, and −2?

Answer 32

now you find f(-x) and count the sign changes again
f(-x) = (-x)^6 −(- x)^5 − (-x)^4 + 4(-x)^3 − 12(-x)^2 + 12
= x^6 + x^5 - x^4 - 4x^3 -12x^2 + 12

- 2 changes of signs

Answer 33

So for the positive would it be 4,2,0 sign changes?

Answer 34

i missed one out for f(x) its 4 sign changes

Answer 35

not sure - i'll have to re check

Answer 36

Ok. So would the answer be positve:4,2,0 and negative 2,0 and complex:6,4,2,0

Answer 37

yea 4,2 or 0 positive roots

Answer 38

Which of the following is a polynomial with roots: −square root of 3, square root of 3, and −2?

Answer 39

x3 − 2x2 − 3x + 6
x3 − 3x2 − 5x + 15
x3 + 2x2 − 3x − 6
x3 + 3x2 − 5x − 15

Answer 40

is the answer B?

Answer 41

yes i think you are right for the first one

Answer 42

so is it B for the second question?

Answer 43

roots sqrt3 - sqrt3 and -2
factors will be
(x + 2)(x - sqrt3)(x + sqrt3)
= (x +2)(x^2 - 3)

Answer 44

expanding gives
x^3 + 2x^2 - 3x - 6

Answer 45

So it would be A?

Answer 46

that is C

Answer 47

really?

Answer 48

x3 + 2x2 − 3x − 6

Answer 49

That one?

Answer 50

yes

Answer 51

I thought it was A. But i believe u

Answer 52

What is the quotient (6x4 − 15x3 + 10x2 − 10x + 4) ÷ (3x2 + 2)?

Answer 53

2x2 − 5x + 2 I got this as an answer

Answer 54

yes?

Answer 55

sorry I got called away
lets see

Answer 56

It's okay:)

Answer 57

What is the quotient (6x4 − 15x3 + 10x2 − 10x + 4) ÷ (3x2 + 2)?
Just in case u needed the question again

Answer 58

yes

Answer 59

looks good

Answer 60

Was I right?

Answer 61

lol - i'm really slow with this one

Answer 62

it's fine:)

Answer 63

Yes you are right

Answer 64

ok
Using synthetic division, what is the quotient (2x3 − 2x − 12) ÷ (x − 2)?

Answer 65

I got this as an answer: 2x2 + 4x + 6

Answer 66

correct

Answer 67

ok
If x = 1 is a zero of the polynomial function f(x) = 3x3 − 8x2 + 3x + 2, which of the following is another zero of f(x)?

Answer 68

i got -1

Answer 69

f(-1) = -3 - 8 - 3 +2 = -12 so its not -1

as the last term is + 2 it might be -2 or 2

Answer 70

both -2, and 2 are answer choices :(

Answer 71

try f(2)

Answer 72

f(2) = 3(8)- 8(4) + 6 + 2 = 24 - 32 + 8 = 0

Answer 73

so its 2

Answer 74

What is the remainder when (3x4 + 2x3 − x2 + 2x − 24) ÷ (x + 2)?

Answer 75

Thank-you:) For this one I got 0 as a answer

Answer 76

you should really be submitting them in different posts ..
but ill do this last one

Answer 77

Oh okay. I'm sorry :)

Answer 78

f(-2) will give you the remainder

Answer 79

so it's not 0?

Answer 80

3(-2)^4 + 2(-2)^3 - (-2)^2 - 4 - 24
= 48 - 16 - 4 - 4 - 24 = 48 - 48 = 0

Answer 81

correct