Posting Freak
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(mathematically)
if cos²(u) + sin²(u) = 1, then does
cos²(2t) + sin²(2t) = 1?
because technically those are double angle formulas (where cos²(2t) = [cos(2t)]².
and if we let u = 2t, then cos²(2t) + sin²(2t) = 1 -> cos²(u) + sin²(u) = 1. but then we cant substitute 2t back in for u since its just a 1 now and nowhere to plug u into.
Posting Freak
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No it's not legal, you're gonna get locked up for 25-life.  WHAT YOU HAVE DONE HERE IS A FUCKING FELONY, A MOCKERY OF ALL THAT IS SACRED AND GOOD!!!
Posting Freak
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relax man. im not quite here yet.
Posting Freak
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butterfli Wrote:relax man. im not quite here yet.
Is that the same black hole our tax dollars go into?
Posting Freak
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butterfli Wrote:relax man. im not quite here yet.
NOOOOOOOOOOOOOOOOOOOOO
why'd ya have to divide by zero?
Posting Freak
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Quantact Wrote:Is that the same black hole our tax dollars go into? 
secretary of US treasury mustve divided by zero.
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If t is a variable and not a function, then yes that's legal.
If t is a function, I'm not 100% sure but I think it's also legal... not sure.
Posting Freak
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butterfli Wrote:secretary of US treasury mustve divided by zero.
They shred cash and stuff lamps with it, what did you expect?
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psychopat Wrote:If t is a variable and not a function, then yes that's legal.
If t is a function, I'm not 100% sure but I think it's also legal... not sure.
the whole problem is (vector) integrating.
i simplified the integral to look like:
inte[sqrt(144(cos²(2t) + sin²(2t)) + 25)]dt
if i did cos²(2t) + sin²(2t) = 1, then it'd look like
inte[sqrt(144(1) + 25)]dt
=inte[sqrt(169)]dt
=inte[13]dt = 13t
the answer and final stepped looked to easy and simple so i wondered if doing that trig thing was legal lol. its suspicious when complicated math problems come out to have simple answers.
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All jokes aside, yeah, that's valid maths.
Posting Freak
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cos²(u) + sin²(u) = 1
Holds valid, as long as the arguments of the trigonometric functions, u, are the same.
So, since u = 2t, it would be true for
cos²(2t) + sin²(2t) = 1
But not true for
cos²(2t) + sin²(3t) = 1
since 2t is not equal 3t (unless t = 0).
And yes, I do believe that is the correct solution for the integral.
Posting Freak
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2008-10-02, 07:28 PM
(This post was last modified: 2008-10-02, 07:30 PM by Worthyness.)
inte[sqrt(144(cos²(2t) + sin²(2t)) + 25)]dt
What you are doing is u substitution. in order for your theory to be viable, you would have to do the following:
u= 2t --> du = 2 dt
so technically the answer you have is wrong since you did not compensate for the 2dt...
But all the other math workings i can't do, since i'm not in a high level calculus class =P
i.e. no clue how to do this... but you can do the u thingy if you compensate for the dt part...
Posting Freak
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You don't have to do u substitution. cos²(2t) + sin²(2t) = 1.
Posting Freak
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Worthyness Wrote:inte[sqrt(144(cos²(2t) + sin²(2t)) + 25)]dt
What you are doing is u substitution. in order for your theory to be viable, you would have to do the following:
u= 2t --> du = 2 dt
so technically the answer you have is wrong since you did not compensate for the 2dt... u was just a random variable. i didnt do u substitution, it was trig substitution/trig identity.
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13t + c

You'd need a specific solution to know what c is.
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I snap. Your getting death row now D:>
QUICK! TO THE ESCAPE POD! LAWYER!
Posting Freak
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Stereo Wrote:13t + c

You'd need a specific solution to know what c is.
it was a definite integral  2u2
thanks to people who answered. people who didnt can go get divided by zero now.
Posting Freak
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uhh sorry I don't do Specialist Math :f6:
Wow... that looks kinda confusing, shame I only do Methods 3/4
Posting Freak
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You know about that 1 over there? I'm pretty sure that means the t's have canceled each other like matter on anti-matter. And you're not doing anything illegal as far as I can tell.
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