# I should have had [chat] prepared!

## Posts

• Arrrrrf. the ivory tower's basementRegistered User regular
ronya wrote: »
ronya wrote: »
Urgh.

So if I have this:

and am given that it is Real, and c is real, and c is not 0 ... how do I figure that out algebraically? I know you can convert to polar form and use de Moivre's theorem to show c is tan of something, but that's the second part of the equation. I'm stuck on whatever the other method is and naturally there are no supplied worked examples for this.

what's that in the corner, it's too small

Sorry here's a bigger one:

I know it's something to do with turning it into a quadratic somehow. But doing that I just get c = 0, which it can't be.

do you want a hint, or an answer

However many hours later, an answer.

tan(2pi/5)

you can use de moivre's, true, but it would be easier to reason geometrically. Multiplication by a complex number is a partial zoom and a partial rotation. To get back to a real number in 5 times, it can only be doing 2pi/5 per multiplication. The adjacent side is one unit long, so the opposite side must be 1*tan(2pi/5) long.

• Laugh hard, run fast, be kindRegistered User regular
Addendum to my baw about the iPhone update last night; now the keyboard has changed the shift key being highlighted to White instead of Dark Grey, making it look like the alphabet buttons and being super confusing to look at after a forever of having this device look a certain way.

Oh brilliant
• Registered User regular
tyrannus wrote: »
Mojo_Jojo wrote: »
Dammit. Today is audit day and I have lab work to do

audit day? hmmmmmmm?

• Gamble a stamp. I can show you how to be a real man!Moderator mod
Jacobkosh wrote: »
I am talking to a girl I know who is currently narrating to me, via hastily-typed IMs, a lesbian groping with her roommate.

This wasn't how I'd planned to spend my 5am, but I mean, I will take it.

is she the gropee

or the groper

gropee

it was entertaining reading while it lasted

• Arrrrrf. the ivory tower's basementRegistered User regular
here is the polar form method anyway

1 = r cos x
c = r sin x

0 = r sin 5x by de moivre

solve (3): 5x = 0 (discarded by assumption x != 0), 2pi, 4pi, 6pi, etc.

x = 2pi/5, 4pi/5, 6pi/5, etc. QED

You can now solve for r, but it's not necessary in this question.

• Registered User regular
oh god oh god i super do not wanna be in work anymore

• Registered User regular
ronya wrote: »
ronya wrote: »
ronya wrote: »
Urgh.

So if I have this:

and am given that it is Real, and c is real, and c is not 0 ... how do I figure that out algebraically? I know you can convert to polar form and use de Moivre's theorem to show c is tan of something, but that's the second part of the equation. I'm stuck on whatever the other method is and naturally there are no supplied worked examples for this.

what's that in the corner, it's too small

Sorry here's a bigger one:

I know it's something to do with turning it into a quadratic somehow. But doing that I just get c = 0, which it can't be.

do you want a hint, or an answer

However many hours later, an answer.

tan(2pi/5)

you can use de moivre's, true, but it would be easier to reason geometrically. Multiplication by a complex number is a partial zoom and a partial rotation. To get back to a real number in 5 times, it can only be doing 2pi/5 per multiplication. The adjacent side is one unit long, so the opposite side must be 1*tan(2pi/5) long.

No that one I got. Apparently I'm somehow supposed to somehow show that its

• He keeps kickin' me in the dickRegistered User regular
Jacobkosh wrote: »
I am talking to a girl I know who is currently narrating to me, via hastily-typed IMs, a lesbian groping with her roommate.

This wasn't how I'd planned to spend my 5am, but I mean, I will take it.

is she the gropee

or the groper

Good to see you Jacob and that you're staying preoccupied.

And now I realize there is no thumbs up icon? Noooooo! Regardless, hi5 for lesbian story there sir.

desc wrote: »
~ * swole patrol flying roundhouse kick top performer recognition: April 2014 * ~
If you have a sec, check out my podcast: War and Beast Twitter Facebook
• rRegistered User regular
This tree isn't putting up with your shit

• Registered User regular
Winky wrote: »
This tree isn't putting up with your shit
First world anarchy.

• Registered User regular
The worlds slowest rebel.

• He keeps kickin' me in the dickRegistered User regular
Jacobkosh wrote: »
Jacobkosh wrote: »
I am talking to a girl I know who is currently narrating to me, via hastily-typed IMs, a lesbian groping with her roommate.

This wasn't how I'd planned to spend my 5am, but I mean, I will take it.

is she the gropee

or the groper

gropee

it was entertaining reading while it lasted

Technically couldn't they have both been gropers?

desc wrote: »
~ * swole patrol flying roundhouse kick top performer recognition: April 2014 * ~
If you have a sec, check out my podcast: War and Beast Twitter Facebook
• Registered User regular
haha my friend got tagged in a pic of him in a bar looking apathetic while wearing a swans shirt

it is the best

• Registered User regular

• Casa GrandeRegistered User regular
tyrannus wrote: »
Mojo_Jojo wrote: »
Dammit. Today is audit day and I have lab work to do

audit day? hmmmmmmm?

hells yeah IRS

his son is da best in the WWE right now

• Arrrrrf. the ivory tower's basementRegistered User regular
edited March 2014
ronya wrote: »
ronya wrote: »
ronya wrote: »
Urgh.

So if I have this:

and am given that it is Real, and c is real, and c is not 0 ... how do I figure that out algebraically? I know you can convert to polar form and use de Moivre's theorem to show c is tan of something, but that's the second part of the equation. I'm stuck on whatever the other method is and naturally there are no supplied worked examples for this.

what's that in the corner, it's too small

Sorry here's a bigger one:

I know it's something to do with turning it into a quadratic somehow. But doing that I just get c = 0, which it can't be.

do you want a hint, or an answer

However many hours later, an answer.

tan(2pi/5)

you can use de moivre's, true, but it would be easier to reason geometrically. Multiplication by a complex number is a partial zoom and a partial rotation. To get back to a real number in 5 times, it can only be doing 2pi/5 per multiplication. The adjacent side is one unit long, so the opposite side must be 1*tan(2pi/5) long.

No that one I got. Apparently I'm somehow supposed to somehow show that its

lol. I missed all the real c < 0 solutions. Well.

are you sure you were supposed to use de moivre, anyway

multiplying out (1+ic)^5 gives c^5 i^5 + 5 c^4 i^4 + 10 c^3 i^3 + 10 c^2 i^2 + 5 c^1 i^1 + 1

imaginary part is therefore c^5 - 10 c^3 + 5 c, which by assumption equals 0. Further, c!=0, so we divide by c to get a quadratic in c^2. Solve for c^2. Take root.

ronya on
• Registered User regular
The Undertaker has let himself go.

• He keeps kickin' me in the dickRegistered User regular
tyrannus wrote: »
Mojo_Jojo wrote: »
Dammit. Today is audit day and I have lab work to do

audit day? hmmmmmmm?

hells yeah IRS

his son is da best in the WWE right now

I'd link it but I can't access twitter on my work pc where the Bella's posted about one of the Bella's being mentioned in Bray's promo last night and thanking him for noticing the plastic surgery work she had done. lol

desc wrote: »
~ * swole patrol flying roundhouse kick top performer recognition: April 2014 * ~
If you have a sec, check out my podcast: War and Beast Twitter Facebook
• Registered User regular
ronya wrote: »
ronya wrote: »
ronya wrote: »
ronya wrote: »
Urgh.

So if I have this:

and am given that it is Real, and c is real, and c is not 0 ... how do I figure that out algebraically? I know you can convert to polar form and use de Moivre's theorem to show c is tan of something, but that's the second part of the equation. I'm stuck on whatever the other method is and naturally there are no supplied worked examples for this.

what's that in the corner, it's too small

Sorry here's a bigger one:

I know it's something to do with turning it into a quadratic somehow. But doing that I just get c = 0, which it can't be.

do you want a hint, or an answer

However many hours later, an answer.

tan(2pi/5)

you can use de moivre's, true, but it would be easier to reason geometrically. Multiplication by a complex number is a partial zoom and a partial rotation. To get back to a real number in 5 times, it can only be doing 2pi/5 per multiplication. The adjacent side is one unit long, so the opposite side must be 1*tan(2pi/5) long.

No that one I got. Apparently I'm somehow supposed to somehow show that its

lol. I missed all the real c < 0 solutions. Well.

are you sure you were supposed to use de moivre, anyway

multiplying out (1+ic)^5 gives c^5 i^5 + 5 c^4 i^4 + 10 c^3 i^3 + 10 c^2 i^2 + 5 c^1 i^1 + 1

imaginary part is therefore c^5 - 10 c^3 + 5 c, which by assumption equals 0. Further, c!=0, so we divide by c to get a quadratic in c^2. Solve for c^2. Take root.

*sigh* god damn it. I kept suspecting it might be that, then thinking "no doing it this way is retarded and would take forever in an exam".

But you're right - obviously it's just the i parts which would make it work.

This is why I like having worked solutions to things.

• He keeps kickin' me in the dickRegistered User regular
Tav wrote: »
The Undertaker has let himself go.

He has a little bit but considering he's only making a handful of appearances on tv a year I can't say I'm surprised.

desc wrote: »
~ * swole patrol flying roundhouse kick top performer recognition: April 2014 * ~
If you have a sec, check out my podcast: War and Beast Twitter Facebook
• Arrrrrf. the ivory tower's basementRegistered User regular
ronya wrote: »
ronya wrote: »
ronya wrote: »
ronya wrote: »
Urgh.

So if I have this:

and am given that it is Real, and c is real, and c is not 0 ... how do I figure that out algebraically? I know you can convert to polar form and use de Moivre's theorem to show c is tan of something, but that's the second part of the equation. I'm stuck on whatever the other method is and naturally there are no supplied worked examples for this.

what's that in the corner, it's too small

Sorry here's a bigger one:

I know it's something to do with turning it into a quadratic somehow. But doing that I just get c = 0, which it can't be.

do you want a hint, or an answer

However many hours later, an answer.

tan(2pi/5)

you can use de moivre's, true, but it would be easier to reason geometrically. Multiplication by a complex number is a partial zoom and a partial rotation. To get back to a real number in 5 times, it can only be doing 2pi/5 per multiplication. The adjacent side is one unit long, so the opposite side must be 1*tan(2pi/5) long.

No that one I got. Apparently I'm somehow supposed to somehow show that its

lol. I missed all the real c < 0 solutions. Well.

are you sure you were supposed to use de moivre, anyway

multiplying out (1+ic)^5 gives c^5 i^5 + 5 c^4 i^4 + 10 c^3 i^3 + 10 c^2 i^2 + 5 c^1 i^1 + 1

imaginary part is therefore c^5 - 10 c^3 + 5 c, which by assumption equals 0. Further, c!=0, so we divide by c to get a quadratic in c^2. Solve for c^2. Take root.

*sigh* god damn it. I kept suspecting it might be that, then thinking "no doing it this way is retarded and would take forever in an exam".

But you're right - obviously it's just the i parts which would make it work.

This is why I like having worked solutions to things.

well, over here in singapore, we refined that to a fine art a long time ago

yeah, answers are a must when revising high school math, I think. Yeah that means you can't force students to revise, since they'll just cheat, but it's absolutely necessary to be efficient when studying

• Casa GrandeRegistered User regular
Gonmun wrote: »
tyrannus wrote: »
Mojo_Jojo wrote: »
Dammit. Today is audit day and I have lab work to do

audit day? hmmmmmmm?

hells yeah IRS

his son is da best in the WWE right now

I'd link it but I can't access twitter on my work pc where the Bella's posted about one of the Bella's being mentioned in Bray's promo last night and thanking him for noticing the plastic surgery work she had done. lol

Yeah I seen it, was reading people who dont understand the difference between him doing that and Cena keep making references to his past characters.

I didnt have the energy to explain how those are worlds apart and that the plastic comment actually work ins into his whole "you're a false idol promos" and isn't a hey you're this goofy guy I hit with a char from behind a door from a shitty stable a couple years back.

• GNU Terry Pratchett Registered User regular
Haphazard wrote: »
So, after I finshed a particularly Swedish novel, I'm listening to The Long War. I quite enjoy the world they've built.

I read the short story Pratchett wrote which eventually became The Long Earth. It was interesting to see what he decided worked and what didn't, and how the collaboration process changed the focus of the story.

[Muffled sounds of gorilla violence]
• Registered User regular
Gonmun wrote: »
Tav wrote: »
The Undertaker has let himself go.

He has a little bit but considering he's only making a handful of appearances on tv a year I can't say I'm surprised.

Wait, is that pic actually The Undertaker? Jesus, I was joking.

• Arrrrrf. the ivory tower's basementRegistered User regular
the sad thing about studying math this way, it grinds to an abrupt halt once math becomes less about technique and more about your ability to define and prove theorems - where your grasp of technique is taken for granted

so that bit can come as a nasty shock

• Casa GrandeRegistered User regular
Tav wrote: »
Gonmun wrote: »
Tav wrote: »
The Undertaker has let himself go.

He has a little bit but considering he's only making a handful of appearances on tv a year I can't say I'm surprised.

Wait, is that pic actually The Undertaker? Jesus, I was joking.

Lol no but the way you said it is actually very much true about Undertaker tho is pushing 50 and in such bad physical shape everything he does has to be incredily over rehearsed.

• He keeps kickin' me in the dickRegistered User regular
Tav wrote: »
Gonmun wrote: »
Tav wrote: »
The Undertaker has let himself go.

He has a little bit but considering he's only making a handful of appearances on tv a year I can't say I'm surprised.

Wait, is that pic actually The Undertaker? Jesus, I was joking.

lol No, but he has actually put on a little weight.

desc wrote: »
~ * swole patrol flying roundhouse kick top performer recognition: April 2014 * ~
If you have a sec, check out my podcast: War and Beast Twitter Facebook
• Arrrrrf. the ivory tower's basementRegistered User regular
more whinging: the reticence of colleges to provide worked answers in applied math problems was absolutely infuriating

yeah okay you can't tossed pointless assessed busywork at us

but i gotta study okay

• Arrrrrf. the ivory tower's basementRegistered User regular
also that question is nasty if the binomial formula wasn't in your precalc syllabus

• Registered User regular
ronya wrote: »
also that question is nasty if the binomial formula wasn't in your precalc syllabus

It's just been years since I've done second year maths, but the lack of worked solutions makes this whole thing laughably inefficent. "Wait a week and hope to god you follow a tutor explaining it" is a ridiculous model.

When I just downloaded the solution manual for my elec. course, suddenly I noticed I was actually getting better at things since I could work around being stuck on one problem.

• Arrrrrf. the ivory tower's basementRegistered User regular
yeesh

yeah that is ridic

• Casa GrandeRegistered User regular
Going to post this again because I can :P
Kiddoroar wanted a fort to sleep in tonight so ladyroar obliged him, here we are reading a book before bed.

• Socially lubricated for your pleasure Registered User regular
Top of the morning to all of you lot, to be sure!

• rRegistered User regular
This episode of Space Dandy is awesome. The entire thing is just presenting this completely surreal alien society formed by intelligent plants, but does so with little subtext or explanation, and so what you see is a series of trippy and incomprehensible scenes in which events occur but you have no basis with which to relate them to our own world because the world depicted is so alien. I love it.

• Registered User regular
ronya wrote: »
yeesh

yeah that is ridic

The funny thing is I was complaining about this to Bulgarian girl, who is tutoring chem students at the moment, and she had one of them complaining about the exact same thing to her. Of course I have numerous problems with the way the chem department does it's marking. It is...unrigorous.

• Registered User regular

One of the saddest things was that when the Undertaker hobbled to the ring to challenge Lesnar, he ducked in under the top rope instead of stepping over it.

Wrestling wrecks bodies like nothing else. I've been listening to Steve Austins podcast and it's just one big string of medical wrecks.

Also IRS other son is NXTs best heel, who essentially is playing a character who is delusional about how much the fans love him.

Steam: SanderJK Origin: SanderJK
• Registered User regular
SanderJK wrote: »
One of the saddest things was that when the Undertaker hobbled to the ring to challenge Lesnar, he ducked in under the top rope instead of stepping over it.

Wrestling wrecks bodies like nothing else. I've been listening to Steve Austins podcast and it's just one big string of medical wrecks.

Also IRS other son is NXTs best heel, who essentially is playing a character who is delusional about how much the fans love him.

Yeah I just listened to the "Rowdy" Roddy Piper interview and man, he gets personal on there with his stories.

• He keeps kickin' me in the dickRegistered User regular
SanderJK wrote: »
One of the saddest things was that when the Undertaker hobbled to the ring to challenge Lesnar, he ducked in under the top rope instead of stepping over it.

Wrestling wrecks bodies like nothing else. I've been listening to Steve Austins podcast and it's just one big string of medical wrecks.

Also IRS other son is NXTs best heel, who essentially is playing a character who is delusional about how much the fans love him.

Taker also underwent a hip replacement last year as well so he hasn't had that going for him from a flexibility stand point. Though at least he's got something to fall back on with his real estate company once he decides to hang up the boots.

Funnily enough, Kane just opened an insurance company with his wife. I wonder how their fire insurance coverage is?

desc wrote: »
~ * swole patrol flying roundhouse kick top performer recognition: April 2014 * ~
If you have a sec, check out my podcast: War and Beast Twitter Facebook
• Registered User regular
Plus both Taker and Kane seem to have been smart with their money.

This discussion has been closed.