/sci/ - Science & Math

[Anonymous No.4101306]

tan^2(x)=2tan(x)

how?

[Josef crossed out the Atlantic !!nUf2NflSAyw No.4101324]

>No domain
No solution.

[Anonymous No.4101319]

it doesn't

[Anonymous No.4101325]

0

[Anonymous No.4101338]

let y = tanx

y^2 = 2y
y^2 - 2y = 0
y(y-2) = 0
y = 0
or
y = 2
tan x = 0
or
tan x = 2

take it from there

[Anonymous No.4101342]

It's not true. Unless you mean you want to find x so that it is true.

Then y^2 = 2y. Solve for y, then solve tan(x) = y.

[Anonymous No.4101426]

where did i go wrong?

[Anonymous No.4101446]

>>4101426
Every fucking where..

[Anonymous No.4101452]

>>4101446
what you mean?

[Anonymous No.4101461]

>>4101426
please tell me you're trolling

else kill me

[Anonymous No.4101474]

>>4101426
Jesus christ, wtf

[Anonymous No.4101484]

>>4101426

Please, put down the pen, step away from the math, and never go anywhere near it again.

[Anonymous No.4101486]

>>4101461
Show me how then, if you know

[Anonymous No.4101515]

wow

[Anonymous No.4101537]

>>4101426
Frankly, you don't make any sense starting from the third line.

[Anonymous No.4101541]

>>4101537

cos^2(x)=1-sin^2(x)
it's derived from sin^2(x)+cos^2(x)=1

I'm trying to get common denominators...

[Anonymous No.4101543]

>>4101426

>GPS data in the EXIF

https://maps.google.com/maps?q=43.842,-76.199&z=15

How's your ice cream, dude?

[Anonymous No.4101549]

>>4101541
That's ok, but why does 1-sin^2(x) appear on the right side of the equation?

[Anonymous No.4101555]

>>4101543
How did you access the exif data?

[Anonymous No.4101559]

>>4101541
why are you trying to get common denominators when you can cross multiply and cancel? why are you cancelling sin^2x with 1-sin^2x? where is cosx on the LHS if you're trying to get common denominators? the entire paper appears to be a bunch of inane babble written down by a three year old's biased interpretation of symbolic manipulation and trigonometry.

[Anonymous No.4101567]

>>4101543
i live in that area

driving to OP's location now to slap him in the face with a page of euclidean geometric trigonometric functions and babby's first algebra

[Anonymous No.4101577]

>>4101543
>trolley ice cream
>trolley
>troll

Fucking brilliant

[Anonymous No.4101582]

How could i live at an ice cream joint?

[Anonymous No.4101588]

>>4101582

Who said you live there? We all like enjoying some ice cream while we utterly fuck up basic algebra.

[fizixfag !!tPJGYMG9r+S No.4101592]

>>4101426

conception

[Anonymous No.4101594]

>>4101577

[Anonymous No.4101598]

>>4101577

[Anonymous No.4101600]

>>4101567
>>4101577

[Anonymous No.4101603]

learn some algebra rules, dude

[Anonymous No.4101608]

You mean just solve it?

<span class="math">\tan^{2}{x}=2~\tan{x}[/spoiler]

<span class="math">\tan{x}=2[/spoiler]

<span class="math">x=\arctan{2}[/spoiler]

By inspection, since both terms have tan(x), we can also come to the alternate solution of x=0.

[Anonymous No.4101611]

>>4101426
The shit stain across your paper, to start with.

[Anoñymous No.4101668]

can I get some help guize?

not a math major, btw

[Anonymous No.4101675]

>>4101577

ilovethisthread.jpg

[Anonymous No.4101683]

>>4101543
I live near there. I hope his retard doesn't rub off on me.

[Anoñymous No.4101699]

>>4101668

please? I just started calculus and this problem is really confusing me. did i do it right? (not homework btw)

[Anoñymous No.4101715]

>>4101699

you guys are fags. whenever someone actually has a math problem that needs solving you just go away becase its to hard for you.

[Anonymous No.4102074]

>>4101608

incomplete.

More liek dis:

<div class="math">\tan^2(x)=2\tan(x)
\tan^2(x)-2\tan(x)=0
(\tan(x))(\tan(x)-2)=0
\tan(x)=0
AND
\tan(x)-2=0
SO
x=n\pi, n\pi+\tan^{-1}(2)[/eqn</div>

[Anonymous No.4102087]

Like this dood

<div class="math">\tan^2(x)=2\tan(x)</div>
<div class="math">\tan^2(x)-2\tan(x)=0</div>
<div class="math">(\tan(x))(\tan(x)-2)=0</div>
<div class="math">\tan(x)=0</div>
AND
<div class="math">\tan(x)-2=0</div>
SO
<div class="math">x=n\pi, n\pi+\tan^{-1}(2)</div>

[Anonymous No.4102115]

>>4102087
>dude jesus woah.jpg

[Anonymous No.4102146]

>>4102087
You assumed the result. Like saying 2=2.

Of course what you wrote is correct, but it is NOT what the OP is asking, he is asking

How can tan^2(x) equal 2tan(x)

Thus you must prove tan^2(x) equals 2tan(x) by ONLY rearranging tan^2(x)

(Assuming it is correct)

Learn.

[Anonymous No.4102164]

>>4102146
except it doesn't, you fucking idiot. the answer would be 'false'. you can solve it symbolically, you then must use the unit circle or numerically solve it.

[Anonymous No.4102170]

>>4102146

It is only true for certain values of x, as shown by the post you tagged.

It isn't a trigonometric identity

[Anonymous No.4102182]

>>4102164

And hence I said (Assume it is correct), some close inspection of course shows that tan^2(x) does NOT equal 2tan(x) for all x in the real numbers.

However your "solution" did nothing to answer the OP's questions; it showed that tan^2(x)=2tan(x) is true for infinitely many points.

Can you see how this would be confusing?

Let's hold back on the insults eh!

[Anonymous No.4102195]

>>4102182

>Let's hold back on the insults eh!
>the insults eh!
>insults eh!
>sults eh!
>lts eh!
>eh!

>EH!
>EH!
>EH!
>EH!
>EH!
>EH!

[Anonymous No.4102244]

Perhaps you should all look at your trig identities

http://www.sosmath.com/trig/Trig5/trig5/trig5.html

[Anonymous No.4102264]

>>4102182
wat

[Anonymous No.4102279]

>>4101603
>>4101426
>math with a pen

i'm not man enough for that

[Anonymous No.4102284]

tan^2(x) = 2tan(x)
tan^2(x) - 2tan(x) + 1 = 1
(tan(x) - 1)^2 = 1
tan(x) - 1 = +-1
tan(x) = 0, 2

Obviously this is not true if x varies over all reals, since the range of tan(x) is continuous over the entire real number line.

[Anoñymous No.4102287]

>>4101668
ok... since this thread is up again... can someone help me with my problem? (re-asserting that it is definately not homework)

[Anonymous No.4102290]

>>4101668
The problem is you assumed 0=1, from this, any "modifications" like adding sin(x) to both sides are valid as they have been precessed by the definition 0=1

In the ZFC axiom (which we use), 0 does not equal 1, thus that proof is wrong from the first line. Beautiful.

[Anoñymous No.4102298]

>>4102290
Jesus. I wasn't "assuming" that 0=1, I was just trying to prove it, whether true or false

[Anonymous No.4102330]

OMGZZZ I KNOW TEH OP!!!!!

[Anonymous No.4102479]

>>4102330
>>4101567
>>4101426
>>4102330

[Anonymous No.4103451]

i love this thread

[Anonymous No.4103462]

>>4101306
I'm assuming you're entry level so I won't be rigorous;
a=tan[x]
a^2=2a
a^2-2a=0
a=<span class="math">\frac{2 +- 2}{2}[/spoiler]
tan[x]=0 -> x = arctan[0]
tan[x]=2 -> x = arctan[2]

[Anonymous No.4103468]

ITT maths noobs pretending to be math pros by overcomplicating a simple problem

pic related, the problem is that of intersecting lines, baby shit

[Anonymous No.4103479]

>>4102479
filename, fuck you...

You know, it might be fun to start putting fake GPS data in the EXIF...