Got Homework?
Connect with other students for help. It's a free community.
Here's the question you clicked on:
 0 viewing

This Question is Closed

etemplinBest ResponseYou've already chosen the best response.0
http://www.sparknotes.com/math/algebra2/complexnumbers/section3.rhtml
 one year ago

asnaseerBest ResponseYou've already chosen the best response.2
do you know what the conjugate of a complex number \((a+ib)\) is?
 one year ago

asnaseerBest ResponseYou've already chosen the best response.2
correct. now notice what happens if you multiple a complex number by its conjugate:\[(a+bi)(abi)=a^2(bi)^2=a^2+b^2\]
 one year ago

asnaseerBest ResponseYou've already chosen the best response.2
i.e. the imaginary parts of a complex number disappear when you multiply it by its conjugate
 one year ago

amarabBest ResponseYou've already chosen the best response.0
okay thanks! just what i needed
 one year ago

asnaseerBest ResponseYou've already chosen the best response.2
so the idea here is to multiply your fraction with something that would result in the denominator losing its imaginary part.
 one year ago

asnaseerBest ResponseYou've already chosen the best response.2
ok  glad you got it! :)
 one year ago

amarabBest ResponseYou've already chosen the best response.0
okay so i did... 6+i(5i) over 5+i(5i) then got 30+6i+5i+i^2 or 30+2i^2 but to the bottom... i ended up with 25+2i^2 and i don't know what to do after that??
 one year ago

amarabBest ResponseYou've already chosen the best response.0
it looks like 30+2i^2/25+2i^2 but i know it's wrong
 one year ago

asnaseerBest ResponseYou've already chosen the best response.2
\[\frac{6+i}{5+i}=\frac{6+i}{5+i}\times\frac{5i}{5i}=\frac{(6+i)(5i)}{(5+i)(5i)}\]\[\qquad=\frac{30+6i5ii^2}{25+5i5ii^2}=\frac{30+ii^2}{25i^2}\]Then (as suggested by @irene22988) use the fact that \(i^2=1\) to simplify further
 one year ago
See more questions >>>
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.