Because i'm too damn tired...(Math help)

[RavenSEAL]

lol @ banking on parents for job.

You know how many people wish they could "bank on their parents for a job" nowadays? More than you can count is you hands, my hands and then some more hands. They told me that if i earn my Bachelors, they will get me a job. it's not like they are just handing it to me because they feel like it. I still gotta pass the interview with HR and do all the training.

 

[Net]

since this thread is already derailed i'll post a catchy song for deriving:

http://www.youtube.com/watch?v=P9dpTTpjymE

 

[TuxDave]

lol @ banking on parents for job.

Hey, if the parents can hook him up then go for it. I know there is a point of personal pride that you try to get as much done on your own but in the end, who cares. If you get a foot in to an amazing position and execute well I bet you'd be wishing you were in his shoes.

 

[RavenSEAL]

since this thread is already derailed i'll post a catchy song for deriving:

http://www.youtube.com/watch?v=P9dpTTpjymE

LOL, epic.

 

[coxmaster]

since this thread is already derailed i'll post a catchy song for deriving:

http://www.youtube.com/watch?v=P9dpTTpjymE

Is it a bad idea to drink and derive?

 

[eLiu]

Having read the OP's posts before, I'm not sure he's bright enough to be in a calculus class. If he is, then asking how to find the derivative of sin(3x) indicates that he's not bright enough to be in a calculus class.

Thus, I've come to the conclusion that what he means is he wants to derive a formula for sin(3x) in terms of sin(x)

Well played! I didn't even consider this possibility. My first reaction was "do you want us to write it with complex exponentials for you...?????" wat.

I prefer to believe that the OP can't differentiate sin(3x) though.

Also OP, I don't care what your HS GPA was/is & how many AP classes you've taken. I promise that my GPA was higher and I aced more AP exams... but really it's pretty irrelevant. B/c HS is irrelevant. And easy.

 

[RavenSEAL]

Well played! I didn't even consider this possibility. My first reaction was "do you want us to write it with complex exponentials for you...?????" wat.

I prefer to believe that the OP can't differentiate sin(3x) though.

Also OP, I don't care what your HS GPA was/is & how many AP classes you've taken. I promise that my GPA was higher and I aced more AP exams... but really it's pretty irrelevant. B/c HS is irrelevant. And easy.

I honestly don't give a shit about your or anyone else's opinions about my grades/life. All i know is that i simply asked for clarification on an issue that we just started going over today, all he said we had to do was read up on it and try to figure it out ourselves before we came into class, it was simply an extra credit assignment and someone always has to make a big deal out of everything in here.

Either way, thanks for all the help for those that contributed, a friend of mine managed to explain it a bit more clearly to me and got the extra point on the final exam.

Mods, feel free to lock this up before it turns into a crap fest.

 

[Taejin]

doing pretty much anything with sin3x at the trig/calc 1/2/3 level should be relatively trivial. if you can't do this and prefer to blame 'im le tired' then you should just quit.

 

[RavenSEAL]

By the way, for those actually interested, this is how it's done:

sin(2o + o) = sin(2o)cos(o) + sin(o)cos(2o)
sin(o + o)cos(o) + sin(o)cos(o + o)
( sin(o)cos(o) + sin(o)cos(o) )cos(o) + sin(o)( cos(o)cos(o) - sin(o)sin(o) )
2sin(o)cos^2(o) + sin(o)( cos^2(o) - sin^2(o) )
2sin(o)( 1 - sin^2(o) ) + sin(o)( 1 - sin^2(o) - sin^2(o) )
2sin(o) - 2sin^3(o) + sin(o) - 2sin^3(o)
3sin(o) - 4sin^3(o)

i don't know if i typed it completely correct, did it fast since i gotta run now, peace.

 

[DrPizza]

By the way, for those actually interested, this is how it's done:

sin(2o + o) = sin(2o)cos(o) + sin(o)cos(2o)
sin(o + o)cos(o) + sin(o)cos(o + o)
( sin(o)cos(o) + sin(o)cos(o) )cos(o) + sin(o)( cos(o)cos(o) - sin(o)sin(o) )
2sin(o)cos^2(o) + sin(o)( cos^2(o) - sin^2(o) )
2sin(o)( 1 - sin^2(o) ) + sin(o)( 1 - sin^2(o) - sin^2(o) )
2sin(o) - 2sin^3(o) + sin(o) - 2sin^3(o)
3sin(o) - 4sin^3(o)

i don't know if i typed it completely correct, did it fast since i gotta run now, peace.

Congratulations. You were able to follow my directions that I posted about 3 hours ago.

@eLiu "B/c HS is irrelevant. And easy." Depends on your teachers. I have one of the smartest calculus classes I've ever had. They seemed to be feeling a little down the other day about how difficult calculus is. So, I told them that college calculus is at about this level (hand hand waist high), and the typical college student is this smart (hand held slightly below waist.) All of you are realize you're this smart (hand held at my head level), so I've raise the level of difficulty to this level (hand held a little above the previous level) because I realize you're smarter than you think.

I believe that if high school was "easy," then your teachers simply didn't try to challenge you enough. Oh, and to make them feel better, we googled for some sample calculus final exams. We ended up looking at a midterm from 2009 at a well known & respected university (selected by the class at random). After we skimmed through it, I heard a "that's it? Are you kidding me??!"

 

[eLiu]

whoops

 

[eLiu]

Congratulations. You were able to follow my directions that I posted about 3 hours ago.

@eLiu "B/c HS is irrelevant. And easy." Depends on your teachers. I have one of the smartest calculus classes I've ever had. They seemed to be feeling a little down the other day about how difficult calculus is. So, I told them that college calculus is at about this level (hand hand waist high), and the typical college student is this smart (hand held slightly below waist.) All of you are realize you're this smart (hand held at my head level), so I've raise the level of difficulty to this level (hand held a little above the previous level) because I realize you're smarter than you think.

I believe that if high school was "easy," then your teachers simply didn't try to challenge you enough. Oh, and to make them feel better, we googled for some sample calculus final exams. We ended up looking at a midterm from 2009 at a well known & respected university (selected by the class at random). After we skimmed through it, I heard a "that's it? Are you kidding me??!"

My point was more that if you do really well in high school, nobody cares once you get into college. And if you do really well in college, nobody cares once you get a job (counting grad school as a job, lol).

As for easy, at least at my HS, teachers in advanced classes taught to a level that was somewhere around their 'average student', if not a lower. In time in college/grad school, I've met some really, truly intelligent people. And I can tell you with certainty that nobody I went to school with (including me) really qualifies as being that smart. Considering that maybe 10-20 students (out of 600ish) went to "top" schools for math/science, the bar wasn't particularly high. So yeah, I agree. Definitely wasn't being challenged enough. That's the case for most people I know *shrug*. But college had plenty of "oh god kill me now" moments

Those of us who liked math did contests for added challenge/skipping class. We were lucky enough to have an extremely bright teacher who was interested & could help us. He was disorganized as hell & a master of procrastination, but he was awesome.

That said, college calculus isn't really hard either? I mean there are a handful of fundamental concepts that are very new when all you've seen before is "x+y=z" algebra. And for me, it was as jarring as moving from "1+2=3" to "x+y=z". But there isn't a ton of stuff there that I would count as hard? Certainly you can ask very difficult computation questions... but no one is throwing Putnam questions at intro-calc students, HS or college level, lol. Calc1 classes that are more real analysis than "integrate this" often do qualify as pretty tough, since rigorous mathematical proof is a big step forward. I never wrapped my head around that stuff fully...

 

[TuxDave]

Those of us who liked math did contests for added challenge/skipping class.

While I had a challenging math teacher in high school, math league was where I went to for math challenges. Then there was also the AHSME followed by AIME which was the test that eventually kicked my butt. Never saw what happened if you did well on that.

 

[RagingBITCH]

What's with every thread in OT turning into a flame war? Honestly.

You should probably call USF, UCF and FSU to complain, because they've all gladly already said yes to my 3.5 GPA that includes 6 AP classes with all 6 exams passed, including a 5 on AP United States History, World History, Spanish Lang and Lit plus a 4 on AP Literature.

Wow...congratulations on a bunch of meaningless high school stats. I don't turn every thread into a flame war - it's people like you that post stuff no one cares about to begin with.

 

[ThatsABigOne]

The derivative of Sin(x)=Cos(x)

Since you have Sin(3x)

You have to take the derivative of the sine, then take the derivative of the inside the parentices by using the chain rule.

COS(3x)(3)=3cos(3x)