SOLUTION: with the help of the quadratic formula, find all the complex roots of each of the polynomials given in exercise 1. iii) z^3 + i

Algebra.Com
Question 194674This question is from textbook An Introduction to Abstract Algebra with Notes to the Future Teacher
: with the help of the quadratic formula, find all the complex roots of each of the polynomials given in exercise 1.
iii) z^3 + i
This question is from textbook An Introduction to Abstract Algebra with Notes to the Future Teacher

Answer by jim_thompson5910(35256)   (Show Source): You can put this solution on YOUR website!
First, perform synthetic division on the polynomial using the test zero . Note: you can easily solve for "z" and find that one solution is

i |  1  0  0   i
  |     i  -1  -i
  -----------
     1  i  -1   0


Since the first three numbers in the third row are 1, i, and -1, this means that




Now simply use the quadratic formula to solve for "z":


Start with the quadratic formula


Plug in , , and


Square to get .


Multiply


Combine like terms.


So the other two solutions are or


===========================================================

Answer:

So the 3 solutions are , , or

RELATED QUESTIONS

Find the roots of each equation using the Quadratic Formula (answered by jorel1380)
find all the complex roots. leave your answer is polar form with arguments in degress.... (answered by stanbon)
Developing and Analyzing the Quadratic Formula This formula, which is called the... (answered by stanbon)
Use the discriminant to determine the number of solutions of the quadratic equation, and... (answered by MathLover1)
Can someone PLEASE help me with this problem?! THANK YOU! Find all the square roots... (answered by Alan3354)
use the quadratic formula to find the roots of each quadratic equation.... (answered by nerdybill)
Find the roots of z^6=1 for z complex. Show that the sum of the roots you found is zero. (answered by Edwin McCravy)
Hi, I need some help with my American School Algebra 2 work. Given X^*3-4x^*2+2x+1=0 A. (answered by Alan3354)
Suppose ax^2+bx+c=0 is a quadratic equation which has real complex roots. Why should it... (answered by richard1234)