A community for students.
Here's the question you clicked on:
 0 viewing
toadytica305
 3 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
toadytica305
 3 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

This Question is Closed

satellite73
 3 years ago
Best ResponseYou've already chosen the best response.1did you factor? you already knew 1 was a zero, from the last question

Callisto
 3 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?

satellite73
 3 years ago
Best ResponseYou've already chosen the best response.1once you factor, you find the other zeros using the quadratic formula

toadytica305
 3 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
 3 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
 3 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

toadytica305
 3 years ago
Best ResponseYou've already chosen the best response.0i get \[(4\sqrt{15}) /2\]

Callisto
 3 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
 3 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
 3 years ago
Best ResponseYou've already chosen the best response.2Sorry :S \[1\pm \sqrt{14}i\]

toadytica305
 3 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
 3 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..
Ask your own question
Sign UpFind more explanations on OpenStudy
Your question is ready. Sign up for free to start getting answers.
spraguer
(Moderator)
5
→ View Detailed Profile
is replying to Can someone tell me what button the professor is hitting...
23
 Teamwork 19 Teammate
 Problem Solving 19 Hero
 Engagement 19 Mad Hatter
 You have blocked this person.
 ✔ You're a fan Checking fan status...
Thanks for being so helpful in mathematics. If you are getting quality help, make sure you spread the word about OpenStudy.