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anonymous
 4 years ago
List all the real and imaginary zeros of
f(x) = x^3+x^2+ 13x  15... 1 is a zero of the function
anonymous
 4 years ago
List all the real and imaginary zeros of f(x) = x^3+x^2+ 13x  15... 1 is a zero of the function

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anonymous
 4 years ago
Best ResponseYou've already chosen the best response.0did you factor? you already knew 1 was a zero, from the last question

Callisto
 4 years ago
Best ResponseYou've already chosen the best response.2I think the question asks to solve f(x) =0 Since the question gives you 1 is a zero of the function. (x1) is a factor. Now, do the division to get the other factor first, can you?

anonymous
 4 years ago
Best ResponseYou've already chosen the best response.0once you factor, you find the other zeros using the quadratic formula

anonymous
 4 years ago
Best ResponseYou've already chosen the best response.0You said (x−1)(x^2+2x+15) This gives zeros of 1, 3, 5, 15?

Callisto
 4 years ago
Best ResponseYou've already chosen the best response.2Nope!~ f(x) =0 x^3+x^2+ 13x  15 =0 (x−1)(x^2+2x+15) =0 So, x1 =0 (1) or (x^2+2x+15) =0 (2) You can solve (1) easily. And solve (2) using quadratic formula!~

Callisto
 4 years ago
Best ResponseYou've already chosen the best response.2For a quadratic equation ax^2 + bx + c=0 \[x=\frac{b \pm \sqrt{b^2  4ac}}{2a}\]^ Quadratic formula

anonymous
 4 years ago
Best ResponseYou've already chosen the best response.0i get \[(4\sqrt{15}) /2\]

Callisto
 4 years ago
Best ResponseYou've already chosen the best response.2It doesn't seems right... \[x=\frac{2 \pm \sqrt{2^2  4(1)(15)}}{2(1)} =?\]

Callisto
 4 years ago
Best ResponseYou've already chosen the best response.2Nope.. \[x=\frac{2\pm \sqrt {56}}{2} = \frac{2\pm 2\sqrt {14}}{2} = 1 \pm 14i\]

Callisto
 4 years ago
Best ResponseYou've already chosen the best response.2Sorry :S \[1\pm \sqrt{14}i\]

anonymous
 4 years ago
Best ResponseYou've already chosen the best response.0Im still not sure how I get the real and imaginary zeros off that...

Callisto
 4 years ago
Best ResponseYou've already chosen the best response.2the real one is 1 the imaginary ones are \[1\pm \sqrt{14}i\] Actually, the question just asks to you to solve f(x) =0 ... I think..
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