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rubah
03-05-2008, 06:54 AM
Oh man I hate them.

After playing with my calculator, I have found out that the limit as x->∞ of the arctan(x) is π/2, the arcsec(x) as x->1 = ∞, and little else.

Anything else I should be aware of before trying to do crazy-seeming Improper Integrals problems that look divergent but they actually converge because goshdarn it, wouldn't you just know the arctan(∞) happens to be π/2?

Momiji
03-05-2008, 08:01 AM
Okay...what the hell is this? I think my brain just short-circuited reading that.

I'm not good at math.

Vivisteiner
03-05-2008, 08:52 PM
Wiki can help: Trigonometric functions - Wikipedia, the free encyclopedia (http://en.wikipedia.org/wiki/Trigonometric_function)

Because I cant. What level is this around?

And what the hell is up with all this trigonometry crap? It was so easy when you just had sin, cos and tan. Then they add csc and cot which is just about all right. And now they have arcsin, arctan, arccos, arccsc, arcsec, arccot!

Whats the point?

Is it just for simplification or something?

Flying Mullet
03-05-2008, 08:57 PM
Wiki can help: Trigonometric functions - Wikipedia, the free encyclopedia (http://en.wikipedia.org/wiki/Trigonometric_function)

Because I cant. What level is this around?

And what the hell is up with all this trigonometry crap? It was so easy when you just had sin, cos and tan. Then they add csc and cot which is just about all right. And now they have arcsin, arctan, arccos, arccsc, arcsec, arccot!

Whats the point?

Is it just for simplification or something?
arcsin is the inverse function of sin; arctan is the inverse function of tan, etc... Once you understand the relationships between them, they're quite simple, actually. And csc = (1/sin), cot = (1/tan) which are pretty straight forward too.

rubah
03-05-2008, 09:58 PM
oh just wait until you get to the hyperbolic trig functions :sarcasm:

you learn trig stuff in trig, and then you use it in calculus because it makes integrating crazy easier/possible. The problem in question was the integral from 0 to ∞ of one over the sum of two squares, which reeks of the arctangent.

Vivisteiner
03-05-2008, 10:27 PM
^Integral from 0 to ∞?

Thats gotta be ∞!

Ehhh, I find differentiation and integration so boring. I mean who gives a damn whether you use forward or reverse substitution, or integration by parts or implicit differentiation. Its not hard, just boring.*


Thats just my rant. Stupid C3 Maths module.


*Actually, it is hard when you dont have a clue what your teacher is on about and then you get set some hw that just screams 'waste of my time!'

rubah
03-05-2008, 10:34 PM
They're not boring because you can do crazy stuff with them xD Also it's π/2 at ∞ :p it never gets bigger than that.

qwertysaur
03-05-2008, 10:40 PM
Don't forget that arcsin and Arcsin are different things. arctan is the whole inverse relationship, while Arcsin is only the part that is a function.

Vivisteiner
03-05-2008, 10:41 PM
@Rubah: I dont even know what that weird π sign means. :(


Maths is horrible. It used to be my friend and then it stabbed me in the back. Mechanics is so much easier. Physics is so much easier. As is Chemistry as is Biology.

After inventing my own mathematical theorem, I havent been very good at maths at all...

Flying Mullet
03-05-2008, 10:47 PM
@Rubah: I dont even know what that weird π sign means. :(
I think that's pi. It's rendered funny in the font she's using, or it's a different character which looks like pi.

Vivisteiner
03-05-2008, 10:49 PM
pi? Is that some kind of fruit?






...Oh, I see.

Tavrobel
03-05-2008, 11:10 PM
Okay...what the hell is this? I think my brain just short-circuited reading that.

I'm not good at math.

It just means that the angle whose tangent is Pi/2 is an infinitely large angle.


... wouldn't you just know the arctan(∞) happens to be π/2?

Sup, asymptotes? I like what you did with tan(90).


Because I cant. What level is this around?

Whats the point?

Is it just for simplification or something?

Anywhere between Calc I and Calc II.

Because people need to differentiate amongst certain functions of a triangle. At this point, things are only as needlessly complicated as people can break them down without blowing up math. arc functions are just inverses.

Arc functions are inverses in a certain region; essentially, you'll limit the function to the necessary two regions that give you principal values. In the case of Sin and Tan, it is limited to quadrant I and IV. Cos is limited to QI and QII.


oh just wait until you get to the hyperbolic trig functions :sarcasm:

reeks of the arctangent.

sinh and cosh are fun.

Integral(1/(a<sup>2</sup> + u<sup>2</sup>))?

Pi is a vegetable. Just like Loony BoB.

rubah
03-05-2008, 11:32 PM
it's alt+p, which I assume is pi. I don't know what else it would be.

Pasted from wikipedia: π
typed from keyboard: π

in a different font: <span style="font-family: Times;" title="Times">π</span>, <span style="font-family: Courier;" title="Courier">π</span>, <span style="font-family: verdana;" title="Verdana">π</span>, <span style="font-family: trebuchet ms;" title="trebuchet ms">π</span>, <span style="font-family: arial;" title="arial">π</span>

Tavrobel
03-06-2008, 12:21 AM
Too bad the first two symbols look nothing like what I've seen of Pi. The first two and the last one in a different font look like what one usually draws for Pi among the people I know. Drawing it any different makes it look too much like n.

Kawaii Ryűkishi
03-06-2008, 12:39 AM
I like Omnislash.














I'm just kidding. You guys enjoy yourselves.

rubah
03-06-2008, 12:44 AM
blame the eoff font then, idk?

rubah
03-07-2008, 01:43 AM
there were like no weird limits on my midterm, so :up: gogogogthreadSUCCESS