/sci/ - Science & Math

There is none.

>>8779456
It's compatible with the bible.
Jesus solves.

>>8779456
could've been better if he wrote
x=2 - 1
x=-2 x=-1

>>8779456
Maybe swapped addition with multiplication?

Looks like common core to me

>>8779456
addition is wrong
x = 2 - 1
x=2 x=1

The student guessed that x=1 is a solution to the equation and made up some shit to make it seem like he solved it.

Had he also bullshitted the other root I would give it full marks.

same as this

>>8779529
yours doesn't reach the correct solution though

>>8779566
well thats just your opinion, sir

take the log (base 3) and the 3 would cancel i suppose
but idk

Reminds me of Wayside School. There's a story of a kid who counts wrong but always gets the right answer. So if he were to count ten things, he would say, "Six, eight, twelve, one, five, two, seven, eleven, three, ten."

>>8779529
>that last part
Why did they have to do it? Why couldn't they just solve it? It was right there. This actually distressed me a little and I'm nit even a math major.

>>8779456
Tutoring a math class for geologists, I see shit like this used unironically all the time :D

>>8779456
Way to eliminate -3 as a solution

2x + x^2 = 3
x^2 + 2x*1 + 1^2 = 3 + 1^2
(x + 1)^2 = 3 + 1
x + 1 = 4^-2 or x + 1 = -(4^-2)
x = 2 - 1 or x = -2 - 1
x = 1 or x = -3

>>8779765
Cool story bro. There should be a school for supernatural math mutants/savants. He'd fit and save the world.

I didn't even look at it and I know its wrong because it should have 2 answers.

>>8779468
"Jesus take the wheel"-logic

>>8779456
This solution makes no sense though, 2x+x^2 is NOT 2x^3

It's best to just put factorise it like
x^2+2x-3=0
so
(x+3)(x-1)=0
so x=-3, x=1

what

>>8780084
>This solution makes no sense though
damn..

>>8779456
now find the other solution

>>8779456

2*x=1 ergo x=0.5

x=1

>>8779456
It's based on the theorem in pic related

>>8779498
>>>/pol/

>>8780579
>>>/trash/

>>8780590
>>>/mlp/

>>8780603
>>>/b/

>>8779456
uhm x*3 =x*x*x
2*x*x*x=3 | :3 =>
2/3*x*x*x=0
so your math is just wrong, you should learn abstractions of mathematical concepts before poisoning minds.
this damn picture annoys the shit out of me

>>8780645
Try plugging x = 1 tho

looks like the student simply cheated to get the answer

>>8779456
Answer checks out. Nice work, OP.

[math]\displaystyle \frac {\mathbb{d}} {\mathbb{d}x} x = \frac {1} {x} x = 1 [/math]

>>8779456
>2x + x^2 = 2x^3
LIterally no mathematical logic here. Just playing to symbols in a seemingly logical way.

OP did nothing wrong

>>8779456
bad logic can lead to accidentally correct conclusions.

i.e. a false statement may imply a true one.

>>8779456
WTF!?
why dont you use the pq-formula?

>>8779456

It's just wrong.

(x^2)+2x-3=0
X=-3, x=1

Should probably stone whoever wrote it. Also, kek at this morons applying calculus to this.

>>8780062
*tips fedora*

>>8779456
2x+x^2=2x^3 implies x=1, but that don't mean it true
formal logic my mans

>>8779456
The cube root of 3 is not 1. 1*1*1=1.

>>8779498
t. flyover

What are quadratics even useful for outside of pure maths?

>>8779456
literally high school math tier

>>8781881
>t. brainlet

>>8781881
>what is parabola

>>8779456
Because -3 is also an answer

>44 posts
fuck you

>>8781976
You made it 45 senpai

>>8780645
It's of 9gag waddaya expect?

>>8779456
One day children will learn this methode at school

>>8781948
I know they form parabolas you retard. I'm asking why is it so important that they're taught in school? What are quadratics and parabolas useful for?

>>8780811
a false statement ALWAYS implies a true statement in any first-order logic

any theory containing a contradiction is complete

>>8782027
When your career will peak with flipping burgers, during the flip the meat flies along a parabola.

>>8782044
While what you say is true, you have not added to the understanding of the discussion. This is the worst type of mathematician.

>>8781881
Lots of things follow a parabolic distribution. I'm not civil, but if I recall a beam with two supports is a very, very close approximation of a beam with four supports (two on top, two on bottom) so only a second degree polynomial is necessary to find it's values. Saves a lot of time, especially since you're just gonna add safety margins onto the damn thing

>>8779529
Z=9
Z=2

What

>>8779456
If you negate logic, you negate errors. As simple as that. We only fail because we apply logic wrongly.

>>8782044
>a false statement ALWAYS implies a true statement

2=3 => 4 = 2*2 = 3*3 = 9

>>8782044
A false statement implies itself, which is by construction not true.

>>8782044
I just reread your post after posting this >>8782715.
Do you mean to say that every false statement has at least one true statement which follows from it, or do you mean to say that every statement implied by a false statement is true?

>>8780610
That's an improvement to /b/

>>8782044
>>8782709
oh wait lel i cant read properly

>>8782724
Every false statement implies all other possible statements, whether true or false. This is the "principle of explosion".

>>8779456
Its troll math. Nonsense

this calculation demonstrates the difference between logic and reasoning

>>8783138
Neat.

> i used the wrong method so i got an F
> b... b... but u got the good result
> teachers are horrible ppl
> jealous of how clever i am.
> i'm clever but lazy and teachers don't understand me this is why i have bad grades
> life is so unfair

>>8779456
Well if x=1 then the steps have merit.

Looks like someone worked backwards. A true reverse-engineering marvel

>>8779456
He guessed the answer, tested it and then made up some bullshit to try and fish for points.

Give him a 1 out of 6.

>>8779456
>LOL LE MAYMAY MATH JOKE

>>8785185
I'm clever but I don't have the motivation

>>8781927
The fuck are you saying? Clearly this is elementary school-level maths. What kind of shithole are you from?

>>8785336
USA the only country that matters

>>8779456
kid found the answer in the back of the book or in the teacher's version, then BS'd the work. I know kids who did shit like this every week in high school.

>>8785352
[xkcd 759]
Handy exam trick: when you know the answer but not the correct derivation, derive blindly forward from the givens and backward from the answer, and join the chains once the equations start looking similar. Sometimes the graders don't notice the seam.

>>8782225
It's another form of a quadratic. So yes, there should be two solutions.

>>8786042
neither is correct

>>8785336
I had to do problems like this to ENTER my first year at Elementary school.

>>8785352
on an exam i had a kid write down the correct answer, and then he scribbled a bunch of bullshit, erased it, and scribbled more bullshit trying to make it as illegible as possible hoping i'd give him (full?) points. instead i gave him half a point (out of 10) for the correct final answer and wrote that the work does not follow.

>>8779456
Systems of equations/Lin Algy assumptions that are very incorrect

2x+x^2=3
and 2x=1
imply that

1+x^2=3
thus
x^2=2

>>8779456