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Svensken
Mar5-11, 06:52 PM
1. The problem statement, all variables and given/known data

Solve the following equations in C :

(a) z^2 + 3z + 2 = 0

3. The attempt at a solution

I thought i should solve the quadratic for z, (z+1)(z+2)=0
and then somehow say that:

1=x+iy

I dont really understand how to go about it, and they want it solved in C. Any hints wil be greatly appreciated!

p.s

This question is a few exercises down, and i know i dont know how to tackle it, it confuses me pretty bad having the conjugate there aswell:

z^2 + 2z + 1 = 0 (where the second z is the conjugate)

Thanks!

Mentallic
Mar5-11, 07:29 PM
So you've factorized the quadratic into (z+1)(z+2). So what are the zeroes of the quadratic then? You've basically solved the question, and even though no complex numbers arised, it is still in C. The solutions are of the form x+0i.

The second question with the conjugate is more difficult. There are actually 4 complex solutions to that equation.
You better get a good grip of the easier questions before tackling those ones or you'll just confuse yourself.