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anonymous
 one year ago
MEDAL AND FAN!!!!
Which of the following represents the zeros of f(x) = 3x3 − 10x2 − 81x + 28
anonymous
 one year ago
MEDAL AND FAN!!!! Which of the following represents the zeros of f(x) = 3x3 − 10x2 − 81x + 28

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UsukiDoll
 one year ago
Best ResponseYou've already chosen the best response.2\[f(x) = 3x^310x^281x+28 \] this?

UsukiDoll
 one year ago
Best ResponseYou've already chosen the best response.2if we need to find 0's then we need the rational root test.

UsukiDoll
 one year ago
Best ResponseYou've already chosen the best response.2The Rational Roots Test (also known as Rational Zeros Theorem) allows us to find all possible rational roots of a polynomial. Suppose "a" is root of the polynomial P(x) that means P(a) = 0. In other words, if we substitute "a" into the polynomial P(x) and get zero it means that the input value is a root. so we take the last term, 28, and find all factors of 28 which is 1,2,4,7,14,28. We also have to take the negative versions as well. So, 1,1,2,2,4,4,7,7,14,14,28,28 just plug these numbers into the equation and stop once you have a 0 there could be more than one root, just one, or none. If we don't have any roots, the test fails.

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0is the answer 7, 4, 1/3

alekos
 one year ago
Best ResponseYou've already chosen the best response.0but the last root lies somewhere between 0 and 1 and I think 1/3 is pretty close

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0answer choices 7,4,1/3 7,4,1/3 7,4,1/3 7,4,1/3

UsukiDoll
 one year ago
Best ResponseYou've already chosen the best response.2hmmm.... let x = 7,4, or 4 and plug it into the equation ... one of them has to produce a zero .we may have to go further like long division to grab the remaining roots

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0im pretty sure it is the last choice

UsukiDoll
 one year ago
Best ResponseYou've already chosen the best response.2did you test it out?

UsukiDoll
 one year ago
Best ResponseYou've already chosen the best response.2because there's a negative root.. and that number is not 1/3

UsukiDoll
 one year ago
Best ResponseYou've already chosen the best response.2so that knocks out two choices.

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0that means it is the third choice because after you test it out it gives you the third choice

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0oops i think i know the answer for this question can you help me with another

UsukiDoll
 one year ago
Best ResponseYou've already chosen the best response.2yeah sure. you actually had the right answer 10 minutes ago XD

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0Which of the following is a polynomial with roots 5, 4i, and −4i

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0f(x) = x^35x^2+20x16 f(x) = x^35x^2+16x80 f(x)=x^320x^2+5x16 f(x) = x^316x^2+80x5

UsukiDoll
 one year ago
Best ResponseYou've already chosen the best response.2wow... it's like we have to use the roots given and plugging in it into the function having x = 5 will make it easier though.

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0so plug 5 for each one

UsukiDoll
 one year ago
Best ResponseYou've already chosen the best response.2try let x = 5 for the second function

UsukiDoll
 one year ago
Best ResponseYou've already chosen the best response.2yeah for each one, but I think I've weeded it out x=5 for the second function

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0i think i can take out the 2nd one and also the the first one

UsukiDoll
 one year ago
Best ResponseYou've already chosen the best response.2first one is nasty... x.x

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0so that is definitely eliminated

UsukiDoll
 one year ago
Best ResponseYou've already chosen the best response.2oh yeah... not to mention that the real root is x=1... not what we need.

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0the answer is the third one

UsukiDoll
 one year ago
Best ResponseYou've already chosen the best response.2the real root I'm getting for that third choice is really bad ... same with the imaginary... the real root is approx.. 20.. we need x = 5,4i,4i cross that out

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0im feeling that my work shows that it is the answer

UsukiDoll
 one year ago
Best ResponseYou've already chosen the best response.2try plugging x = 5 for the second function you have and tell me if your result is 0 f(x) = x^35x^2+16x80

UsukiDoll
 one year ago
Best ResponseYou've already chosen the best response.2then that's the function. since the result became 0... for x = 5... then the roots x =4i, 4i work as well.
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