Complex (imaginary) Numbers Part 1

I introduce complex numbers, show how i-squared is -1, show how to graph them on the argand diagram, and then go through a number of algebraic examples showing how to work with them.

[jackie]

Love it when I'm answering the question in the video outloud and the Prof replies "Yeah it is." Lol. Too funny.

[profrobbob]

Sure you would...YOU took the extra time to seek out additional help and I was just lucky enough for you to find my channel to watch! Thanks for your support and please share my channel with your friends:D

[profrobbob]

Complex numbers won't seem so complex now that they are Closed Captioned:)

[asalm]

I watched most of your lectures in my opinion its very useful, faced many difficulties in complex numbers but when i followed your lectures i understand it, thank you very much 😌😌
Asal, Iraq 😌😌

[THEQuantumPolkaDots]

Math is so much fun! Especially thanks to your videos!

[therbeing]

hi! why didn't u cancel out 21i as u did 10i in the previous example?

[Winter-odwl]

You are GREAT!!! I'm going to tell my classmates (notice how I didn't say friends haha)
about you tomorrow because our teacher doesn't know how to teach. She makes things SOOOO complicated :/
PS: I subscribed :D

[sheet-son]

Rob bob in da house. If you watch these before class you feel like a genius when you are the only one in the room who isn't looking sideways at the board. His precalc playlist follow my book section by section in order, you can't really ask for much more than that. Thanks prof rob bob, you really have taught me a lot

[profrobbob]

Imaginary numbers are funny...right. We spend all this time reminding you that you can't square root a negative number...and forget to mention this is only true if you wish to find real solutions. We then come back and say the sqrt(-1) is i. i squared is sqrt(-1) x sqrt(-1). The square roots cancel and you are left with -1. Remember when dealing with complex numbers you are not limited to dealing with just real numbers.

[profrobbob]

Even those two trinomials are conjugates, you don't multiply them any differently then any other polynomial expressions. If you need more examples, I have a video Multiplying Polynomials Distributive Property. I would multiply the two conjugates together first, remember that i^2 = -1, and then multiply in your x-3.

[profrobbob]

I have the best wife ever...and she doesn't MAKE me do anything:) Thanks for "liking" my vidz and showing your support by subscribing and sharing!! (and for commenting and watching more than one...LOL)...keep your eye out for the funny shirts, and the "Tarrou's Chalk Talk" t-shirts!

[profrobbob]

I hope I can continue to improve and enjoy math more:) Together...let's make "Math FUN!"..hahah:D...and thanks for watching and sharing my channel with your friends.

[profrobbob]

Yes...just go the homepage of my channel and use the little search window in the upper right hand corner to search quadratic equations in my channel.

[profrobbob]

Wow...thank you. Let's see, a highly motivated student who seeks out extra help when needed and is nice...yep I wish I was your teacher too:):):)

[profrobbob]

You're welcome...please come back next time you need help and be sure to support and subscribe in order to help me groW and share with others!

[profrobbob]

The commercials are the only thing helping to support my efforts in making these videos...so you are going to need to deal with them:)

[profrobbob]

Thank you...and thank you too for adding these two videos to your likes list...I appreciate the support!

[profrobbob]

Wait until you see some of the other shirts I wear! I hope you still found my video helpful.

[profrobbob]

...I just noticed that you subscribed, thanks for your support!

[nathanstrubel]

This video really helped. I went back to school for engineering after not being in school for 10 years and all your videos helped me brush up on my math. You're a lifesaver!