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No.10823[D]

Math is fun! Post anything math-related, fun proofs, jokes, youtube vids and the likes
I will start by proving that there can't be one biggest prime number. It's a pretty simple and fun proof
Let's assume that there is a biggest prime number. Now, if this assumption leads us to a contradiction, then it means that the assumption itself is impossible, in other words, that there can't be a biggest prime number
So, assuming there is a biggest prime number, it means that prime numbers are finite (They are at most as many as the biggest prime number)
Now, if we take ALL the prime numbers and multiply them together, we get a number which is divisible by them all.
So now, let's add 1 to it. The result is not divisible by any prime number  so it's prime, and is also clearly bigger than the "biggest" number we had before. Contradiction!

 A prime number is a natural number that is only divisible by itself and one (except 1 itself, which is usually not considered prime). So, 2 is prime, 17 is prime, 15 isn't (it's divisible by 3 and 5)

 if A is divisible by B, then A+1 isn't (except for B=1, but that's not our case because 1 isn't prime)

Here's something more complicated but better shown and explained: https://www.youtube.com/watch?v=wO61D9x6lNY

Tune in next time for a (broken) proof that 1 + 1 doesn't = 2. You'll be able to check your skills to see if you can find the error!

No.10824[D][DF]

does 2+2=4

You rolled the number 152848094 (no dubs or higher)

No.10836[D][DF]

>>10824
No, 2+2=0
Let me prove:
So, let's have two variables, a and b, so that a=b=2
it must be that a^2 = b^2 (by "^2" I mean squared)
then a^2 - b^2 = 0
so (a+b)(a-b) = 0
(a+b) = 0 / (a-b) = 0
because 0 divided by any number equals 0
(a+b) = 0
Remember how we said that a=b=2?
2+2=0
Learn your basic maths kiddo

No.10839[D][DF]

my brain hurts

No.10843[D][DF]

>>10839
alright alright. I'll tell what's wrong. Spoiled so people can try figuring it out themselves
[spoiler]In this step:
>(a+b) = 0 / (a-b) = 0
We divided by 0. You can't do that
[/spoiler]
I mean I get it it's probably awful reading text math. Probably should've posted pics instead. oh well

No.10844[D][DF]

>>10843
dammit, I knew it had something to do with that step.

No.10846[D][DF]

>>10836
OH SHI-

No.10853[D][DF]

>>10843
Speak for yourself. In America, we divide by whatever we want.

No.10977[D][DF]

>>10853
Shut up tailsteak

No.11066[D][DF]

I've written a python program which seems to be able to calculate the golden ratio to arbitrary precision

from decimal import *
# golden ratio calculation
def golden(digits): # digits is the number of digits desired
getcontext().prec = digits
epsilon = Decimal("1e-%d" % digits)
a = Decimal(0)
b = Decimal(1)
prevrat = Decimal(-1)
while abs(a/b - prevrat) > epsilon:
prevrat = a/b
c = a + b
a = b
b = c
return b/a

In like about minute it computed correctly 10000 digits on my laptop
It's probably a pretty inefficient technique, but I had fun writing it

No.11067[D][DF]

>>11066
Forgot to say. I checked the correctness here: https://nerdparadise.com/math/reference/phi10000
All the digits matched

No.11072[D][DF]

>>11066
>>11067
Ok here's a non-retarded version which is exponentially faster

def golden2(digits):
getcontext().prec = digits
return (Decimal(1) + Decimal(5).sqrt())/Decimal(2)

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