is this legal?
#1
(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.
Reply
#2
No it's not legal, you're gonna get locked up for 25-life. Hothead WHAT YOU HAVE DONE HERE IS A FUCKING FELONY, A MOCKERY OF ALL THAT IS SACRED AND GOOD!!! Mad
Reply
#3
relax man. im not quite here yet.

 Spoiler
Reply
#4
butterfli Wrote:relax man. im not quite here yet.

 Spoiler

Is that the same black hole our tax dollars go into? Rolleyes
Reply
#5
butterfli Wrote:relax man. im not quite here yet.

 Spoiler

NOOOOOOOOOOOOOOOOOOOOO

why'd ya have to divide by zero?
Reply
#6
Quantact Wrote:Is that the same black hole our tax dollars go into? Rolleyes

secretary of US treasury mustve divided by zero.
Reply
#7
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.
Reply
#8
butterfli Wrote:secretary of US treasury mustve divided by zero.

They shred cash and stuff lamps with it, what did you expect? Rolleyes
Reply
#9
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.
Reply
#10
No but this is:
 Spoiler
Reply
#11
All jokes aside, yeah, that's valid maths.
Reply
#12
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.
Reply
#13
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...
Reply
#14
You don't have to do u substitution. cos²(2t) + sin²(2t) = 1.
Reply
#15
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.
Reply
#16
13t + c

Tongue

You'd need a specific solution to know what c is.
Reply
#17
I snap. Your getting death row now D:>

QUICK! TO THE ESCAPE POD! LAWYER!
Reply
#18
Stereo Wrote:13t + c

Tongue

You'd need a specific solution to know what c is.

it was a definite integral Tongue2u2

thanks to people who answered. people who didnt can go get divided by zero now.
Reply
#19
uhh sorry I don't do Specialist Math :f6:

Wow... that looks kinda confusing, shame I only do Methods 3/4 Frown
Reply
#20
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.
Reply


Forum Jump:


Users browsing this thread: 1 Guest(s)