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anonymous
 5 years ago
Find a polynomail equation with real coefficients that has the given zeros.
15i and 1+5i
anonymous
 5 years ago
Find a polynomail equation with real coefficients that has the given zeros. 15i and 1+5i

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amistre64
 5 years ago
Best ResponseYou've already chosen the best response.015i + n = 0 1+5i +m = 0 n= 1+5i m= 15i (15i 1+5i) (1+5i 15i)

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.01 +5i 1 5i 5i 25i^2 +5i +25i^2 1 5i +1 +5i 5i +25i^2 5i 25i^2

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.0guess it aint gonna work out like i thought :) gotta head to marketing class now; Ciao :)

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0\[ f(x) = (x(1+5i))(x(15i)) \] \[ = x^2  x(15i) x(1+5i) + (1+5i)(15i)\] \[ = x^2 x +5xi  x  5xi + 1 5i + 5i  25i^2\] \[ = x^2  2x + 1 + 25 \] \[ = x^2  2x + 26 \] \[ \rightarrow f(15i) = 0, f(1+5i) = 0\]

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0When you are doing this problem: I understand the first equation is just subtracting from x then the secong equation you are distributing... why do you add the additonal (1+5i)(15i)??

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0It's all the same equation. I didn't add the (1+5i)(15i). That term is the result of multiplying the last term in each factor.. \[ (a  b)(a  c) = a^2 ac ab +bc\] Where b in this case is (1+5i) and c is (15i)

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Ok..I dont understand. But thank you so much for you help. I have the answer just not sure how I got it... thanks again.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Well wait. Which part don't you understand?

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0It doesn't do any good to have the answer and not understand how you got it. Otherwise you won't be able to use this tool on more complicated tasks.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Do you agree that \[ (xa)(xb) = x^2  ax bx +ab \]

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Yes I agree. That would be just simply distrubtng....

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Right. Do you also agree that if x=a or x=b then the product (xa)(xb) would be 0 because one of the factors would be 0?

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Kinda.. because I dont know where the zero comes from??

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0\[ If\ x = a, then\ (xa) = (aa) = 0 \rightarrow (xa)(xb) = 0*(ab) = 0\]

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Thanks for your help.. I dont want to waste anymore of your time...

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0... You're not wasting my time. Did you understand my last sentence?

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0\[ \rightarrow \] just means 'therefore'

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Let x = a. Then (xa) = (aa). (aa) = ?

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Yes. a  a = 0. No matter what 'a' is.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Ok.. so now that I know that.. what signifigance does that have in my problem?

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0So what we're saying is that when x = a, (xa) = 0. If (xa)=0 then (xa)(xb) would be 0*(xb) which is?

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0The point of the problem is to find a polynomial that has 2 roots. That means that there are two different values for x at which the polynomial will be 0. We construct such a polynomial by writing an expression which has two factors (xa)(xb) Where a and b are the two roots (0's). When x is equal to either a or b, the whole expression will be equal to 0.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Does that make sense?

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Thanks for your help. But I really need to go. Im not getting it. But appreciate your help so much...

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Give it some thought. And try to follow through what I've written. If you have questions, feel free to come back and ask.
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