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Quick mafsStolen 🏅🏅 (i.redd.it)

submitted by AmazingSloth26

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[–][deleted] 274 points275 points  (9 children)

I was today years old when I finally looked closely enough at this meme to see the quadratic equation.

[–]joske_the_great 69 points70 points  (8 children)

How tf did those mathematicians discover formulas like these? Its like one day they're shitting at the toilet and randomly thought: b2 -4ac must used to determine the type of root

[–]iliekcats- 39 points40 points  (1 child)

I mean, it could possibly be graphed and the equation taken from there, example below:

​

x y
1 1
2 3
3 6
4 10
5 15

​

For every number, the multiplication is:

1 (x)*1 = 1 (y)

2 (x)*1.5 = 3 (y)

3 (x)*2 = 6 (y)

4 (x)*2.5 = 10 (y)

​

The multiplication increases by 0.5 per thingy

the equation for the multiplication can be said as:

x/2 + 0.5 (1/2=0.5+0.5=1, 2/2=1+0.5=1.5, etc)

This means that the finished result would be:

​

x*(x/2+0.5)=y

Of course this is much more confusing for more insane formulas but eh you get the gist of it

[–]Purple_Lordx 3 points4 points  (0 children)

Also you could drive it by completing the square, which isn't too hard to figure out I don't think? Although it's hard to get that perspective

[–]here4pewdiepie 19 points20 points  (0 children)

Newton after getting hit by an apple be like

[–]AmazingSloth26[S] 9 points10 points  (1 child)

I know exactly what you mean. But to answer your question, the quadratic formula itself is fairly easy to derive from ax2+bx+c. To get the determinant you use the b2-4ac like you said. Well in the quadratic formula this is under a square root. If Δ < 0 you’ll have a negative square route, so no real routes. If it’s 0 you’ll simply have no square route so it’ll be one real root. And if it’s > 0 you’ll get 2 real roots as the square root is + or - . But yeah, there’s some formulas where I can’t comprehend how someone just thought of that.

[–]rishabhgghosh 2 points3 points  (0 children)

You can probably derive it backwards with a Vietaesque approach. The margins pretty small but I'll try. ax2+bx+c=0 Must be factored into two factors in the C set and it follows by construction.

x1+x2=-b/a (from factoring) x1*x2=c/a (from factoring) ------- 1

That means I will finish this when I get off mobile lol.

[–]NewbornMuse 3 points4 points  (1 child)

tl;dr you just complete the square if you know what that means. In detail:

ax2 + bx + c = 0; factor out a

a[x2 + b/a * x + c/a] = 0; Now we have that a * stuff is 0. Since a isn't 0 (otherwise it's not a quadratic in the first place), the stuff has to be 0. That gives us:

x2 + b/a * x + c/a = 0; Now we complete the square. Basically, you substitute x2 + b/a = (x + b/2a)2 - b2/4a2 [you can verify that the latter is true by multiplying out]

(x + b/2a)2 - b2/4a2 + c/a = 0; now we have a square involving x and then some other stuff not involving x. better to move the other stuff to the other side.

(x + b/2a)2 = b2/4a2 - c/a; now we prepare to combine the two last terms by extending to the same denominator. c/a = 4ac/4a2

(x + b/2a)2 = b2/4a2 - 4ac/4a2

(x + b/2a)2 = (b2 - 4ac) / 4a2; now we have a pure square on the one side, now we can take square roots! Remember that taking the square root on both sides can mess up your signs, so we write:

x + b/2a = +/- sqrt((b2 - 4ac) / 4a2); now on the right side 4a2 is a perfect square.

x + b/2a = +/- sqrt(b2 - 4ac) / 2a; now we move the b/2a to the other side...

x = -b/2a +/- sqrt(b2 - 4ac) / 2a = (-b +/- sqrt(b2 - 4ac))/2a

QED.

[–]joske_the_great 0 points1 point  (0 children)

What

[–]Dads_Spaghetti69 0 points1 point  (0 children)

you can rearrange the general form for a quadratic ((ax2)+bx+c=0) to get x as the subject which leaves you with the quadratic formula

[–]Faburitsu_io 46 points47 points  (7 children)

Real talk, I wish I could like math more to be better at it.

[–]BlondThubder12 11 points12 points  (3 children)

I know this might seem counter- intuitive, but i started liking math when i watched videos explaining the wonders of math, for example Eulers number (e), why was it named like that, whats its purpose and so on... these videos helped me appreciate how much mathematics are involved in the world. And it gave me a new perspective where math is my favorite subject.

[–]satisfiction_phobos 1 point2 points  (1 child)

Graham's number on Numberphile really did it for me.

[–]wutx2 1 point2 points  (0 children)

Grandma's number on the fridge gave me warm fuzzies.

[–]goddess_steffi_graf 0 points1 point  (0 children)

iirc there are several numbers named after Euler and e is not one of them

[–]ProfessorPetrus 21 points22 points  (0 children)

Gotta practice it to be better. Math don't care if you like it or love it.

[–]AmazingSloth26[S] 2 points3 points  (0 children)

As others have said, find some good videos that make it fun. Veritasium, numberphile and zac star are good places to start. If you want to actually learn the maths, then there are plenty of amazing videos online. I think the issue people have with maths is that it’s either too hard to begin with so they quit without really working on it, or they learn fundamental ideas about maths at school but get bored quickly. If you can stick with the boring bits at the beginning it opens up a whole new world that is really interesting. If all of that doesn’t excite you, at least you’ll be able to understand maths memes, which is pretty cool.

[–]Mrifix 0 points1 point  (0 children)

I'm alright in math, I used to be better but idk why I get a rush of dopamine when I solve something hahaha. Math is one of the most satisfying thing in the world when you manage to understand or solve something

[–]gabrrdt 9 points10 points  (1 child)

r/suddenlycaralho

[–][deleted] 0 points1 point  (0 children)

Huzzaz! Um br!

[–]Multiguneur 9 points10 points  (1 child)

The answer is yes. No need to thank me

[–]UnderstandingPale597 0 points1 point  (0 children)

Jesus is always the answer.

[–]cherryasss 9 points10 points  (0 children)

I've been seeing this meme for two years and I always thought it was some high level complex math. But now upon closer inspection I find that this is just 10 grade math. Damn..

[–]ifckfckerwhofcksfish 3 points4 points  (0 children)

I dont want to be rude but Fuck u all i still have vacation and u are all trowing some weird math shit at my brain

[–]Dr-sniffles 3 points4 points  (0 children)

This is the first time I looked at this meme closely and realised the equations are correct.

[–]lexluther4205 4 points5 points  (13 children)

We get it opop you understand math 🤡

[–]AmazingSloth26[S] 36 points37 points  (12 children)

Smh, the angles aren’t even in radians.

[–]Benjjy124[🍰] 5 points6 points  (10 children)

Imagine using radians; Cringe.

[–]satisfiction_phobos 5 points6 points  (9 children)

A student once asked our physics professor why we don't use radians.

Professor was like "Tell me, what is one radian?"...

Student understood. We understood.

[–]injuredflamingo 2 points3 points  (2 children)

i still dont understand it lmao am i dumb?? 180 degrees right?

[–]BlueKayn29 3 points4 points  (0 children)

pi radians is 180 degrees

[–]mfwhy000 2 points3 points  (0 children)

Yeah 180° and then it just magically shifted to pi and the rest is hist- trigonometry

[–]AmazingSloth26[S] 1 point2 points  (5 children)

Degrees is nicer, till you have to use it with calculus

[–]Benjjy124[🍰] 0 points1 point  (4 children)

Nah we use degrees for calculus; I am in UK though.

[–]AmazingSloth26[S] 1 point2 points  (3 children)

I’m also in UK. Not sure where your level stands in maths, but in calculus you are insane if you don’t use radians. Here’s the way I see it: a right angle is 90 degrees. But why? Why not 10, or 25? With radians you use the arc length on the unit circle. On the unit circle you have a radius of 1. The circumference of a circle is 2pir. The radius is 1 and so a full circumference is 2*pi. From that you can work out the equivalent of say 60 degrees as being pi/3 etc. These you would use in calculus. Hope that helps

[–]satisfiction_phobos 0 points1 point  (2 children)

In day to day life radians make no sense.

What is 13 degrees in radians?

What is one radian?

Impractical

[–]AmazingSloth26[S] 0 points1 point  (1 child)

Day to day life it absolutely makes no sense you are right. I don’t think I could live with radians on everything

However, all degrees do have a corresponding radian. You can convert between the two with some equations.

To convert degrees to radians you divide by 180 them multiply by pi. Then the reverse for radians to degrees.

[–]satisfiction_phobos 0 points1 point  (0 children)

I know that. :)

[–]undeniably_confused 1 point2 points  (1 child)

That's no the root of the quadratic formula, it's the regular quadratic formula they just assigned a variable to part of it

[–]carbonclay 0 points1 point  (0 children)

If this is a troll, you have actually ascended beyond god level.

If not, then have to break it to you, the quadratic equation is literally used to find the root of the quadratic equation lmao?

[–]Llorto 1 point2 points  (0 children)

I have never taken her face so seriously before

[–]somebody_zaza 1 point2 points  (0 children)

r/mathmemes

[–]OchakoIsWaifu 1 point2 points  (0 children)

Holy shit never noticed this

[–]czareson 0 points1 point  (1 child)

Sorry man but I'm not in high school and don't understand a shit

[–]czareson 0 points1 point  (0 children)

Oh wait i can understand the first one

[–]OllieChaos -1 points0 points  (0 children)

u/repostsleuthbot Edit: the bot is banned from the sub but OH BOY... THIS IS THE 29TH TIME IT'S BEEN POSTED

[–][deleted] 0 points1 point  (1 child)

Assuming the radius is, let's say, 5, and pi is 3.14, and the height is 6, then the volume is 157 units.

[–]Illustrious-Hamster8 0 points1 point  (0 children)

The fact that I now know what all those equations means makes me sad cuz now I know I’m not ready for cal 2

[–]-SunSh1ne- 0 points1 point  (0 children)

Wow, I never actually looked what those symbols said. Nice!

[–]One-Rich-7696 0 points1 point  (0 children)

Hi Thais person os not Julia Roberts. Os an Brasílian women

[–][deleted] 0 points1 point  (0 children)

This is actually a really smart antimeme well done

[–]AngelicForce01 0 points1 point  (0 children)

Brothers and sisters, I ain't dumb but I also can't do quick math like that.

[–]Siddeshthapa 0 points1 point  (0 children)

It's incredible that I used to solve and understand all that shit once.

[–]Kermit_Memelord 0 points1 point  (0 children)

But on paper

[–]avery5712 0 points1 point  (1 child)

Whoa! Does that mean math equations just float through the air like star wars expositions?

[–]AmazingSloth26[S] 1 point2 points  (0 children)

Must do. Photographs can’t lie /s

[–][deleted] 0 points1 point  (0 children)

Two plus two is four. Minus one that's three. Qwik maffs