this post was submitted on 11 Oct 2023
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submitted 11 months ago* (last edited 11 months ago) by hypertown to c/[email protected]
 
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[–] mumblerfish 142 points 11 months ago (8 children)

Same trick will work next year too!

[–] [email protected] 53 points 11 months ago (2 children)
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[–] [email protected] 5 points 11 months ago* (last edited 11 months ago) (2 children)

Brilliant, now I wonder what ages this works for, I figured only 1 and 2, but then I realised we could write the father's age in other bases..

1 = 2^0 (20 b10)

2 = 2^1 (21 b10)

3 = 3^1 (31 b7 = 22)

6 = 6^1 (61 b4 = 25) if they are lucky the grand father will be 61 that year :-D

8 = 2^3 (23 b12 =27)

9 = 9^1 (91 b3 = 28)

14 = 14^1 (141 b4 = 33)

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[–] TheBat 116 points 11 months ago (2 children)
[–] Jackcooper 54 points 11 months ago (1 children)
[–] [email protected] 29 points 11 months ago (1 children)
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[–] Daft_ish 12 points 11 months ago

Don't worry it works for all factors of ten. Like 1^0^ = 1

[–] [email protected] 71 points 11 months ago (1 children)

Took me too long to realize the 0 can be an exponent.

[–] spacesweedkid27 11 points 11 months ago (2 children)

Wait until you hear fractions can be exponents and what that means in realtion to power rules and roots.

Then wait until you hear irrational numbers can be exponents and what that means for irrational powers of irrational numbers.

And then wait until you about complex numbers being able to be exponents and loose your mind about e^(iπ) being -1

[–] plz1 7 points 11 months ago (1 children)

That's the part where I nope right out. Math isn't something I ever enjoyed, and getting into fractional exponents sounds like a nightmare to me. I also was unaware 0 is a valid exponent.

[–] LemmysMum 5 points 11 months ago* (last edited 11 months ago)

Thankfully math doesn't technically get harder than understanding counting and key mathematical operators (+ - x /), there's just more steps.

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[–] [email protected] 68 points 11 months ago

Ah yes. How fitting for a young new person in the world. A reminder that 2°C of warming above the pre-industrial mean would be catastrophic, but also is a good lower-limit of what to expect based on current intentions.

[–] Random_user 51 points 11 months ago (3 children)

Theres no way that a dude that got a girl pregnant at 18 would understand this.

[–] blanketswithsmallpox 31 points 11 months ago* (last edited 11 months ago) (1 children)

I know plenty of smart people pretending to be Winnie the Pooh while elbow deep in honey pots. Just because you weren't fucking doesn't mean other nerds weren't lol.

Sucks to be you nerd.

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[–] [email protected] 15 points 11 months ago

He probably didn't. Her dad (the grandpa) made the balloons.

[–] [email protected] 14 points 11 months ago

What?! Impossible to start a family at 18 and also enjoy mathematics?

Not everyone who has unprotected sex at 18 (or with an 18 yr old) is some numbskull just going at it for unscrupulous pleasure.

(As another reply also pointed out: the pun was crafted by the OP's dad, not the 1yr-old's dad; and OP could be the child's mum or dad)

[–] TheGiantKorean 49 points 11 months ago (4 children)
[–] [email protected] 24 points 11 months ago (1 children)
[–] [email protected] 6 points 11 months ago

They'll get complexes

[–] [email protected] 20 points 11 months ago

Kind of hard to define but refer to themselves as I?

[–] [email protected] 5 points 11 months ago

Sounds pretty complex

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[–] ThatWeirdGuy1001 22 points 11 months ago* (last edited 11 months ago) (15 children)

I know I'm bad at math but I don't understand how 2x0=0 but 2^0=1

How are they different answers when they're both essentially multiplying 2 by zero?

Someone with a bigger brain please explain this

Edit: I greatly appreciate all the explanations but all they've done is solidify the fact that I'll never be good at math 😭

[–] [email protected] 29 points 11 months ago (2 children)

subtracting one from Exponent means halving (when the base is two):

2⁴ = 16 2³ = 8 2² = 4 2¹ = 2 2⁰ = 1

It's a simple continuation of the pattern and required for mathemarical rules to work.

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[–] Globulart 16 points 11 months ago* (last edited 11 months ago) (1 children)

This isn't strictly speaking a proof, but it did help me to accept it as it demonstrates the function that makes it 1.

2^3 = 2x2x2

2^2 = 2x2

(2^3)/(2^2) = (2x2x2)/(2x2) = 2

= 2^(3-2)

In general terms:

(x^a)/(x^b) = x^(a-b)

If a and b are the same number this is x^0 and obviously (x^a)/(x^a) is one because anything divided by itself is 1.

Hope that helps

[–] hemmes 5 points 11 months ago (7 children)

Yes, of course, obviously...JFC, what??

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[–] [email protected] 15 points 11 months ago* (last edited 11 months ago)

Easiest explanation I can think of using the division law for exponents:

Since we can use any number for the initial fraction, as long as the denominator is the same as the numerator, any number to the zeroth power is equal to 1. In general terms, then, for any number, x:

[–] [email protected] 15 points 11 months ago (1 children)

0 is the neutral element for addition. This is why when we have a number then 0 + number = number (0 doesnt change the value in addition) and why 0 x number = 0 (if you add a number 0 times you will have 0). (Multiplication is adding one of the numbers to itself the number of times designated by the second number)

The same way 1 is the neutral element for multiplication. This is why when you have some number then 1 * number = number. This is also why number^0 = 1 (if you never multiply by a number you are left with the neutral element. It would be weird if powering by 0 left you with 0 for example because of how negative powers work)

This is the level 1 answer.

The level 0 answer is that it is this way because all of mathematics is a construct designed to ease problem solving and all people collectively agreed that doing it this way is way more useful (because it is)

Choose which one you want

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[–] [email protected] 8 points 11 months ago

I see other people have posted good explanations, but I think the simplest explanation has to do with how you break down numbers. Lets take a number, say, 124. We can rewrite it as 100 + 20 + 4 and we can rewrite that as 1 * 10^2 + 2 * 10^1 + 4 * 10^0 and I think you can see why anything raised to the 0th power has to equal 1. Numbers and math wouldn't work if it didn't.

[–] [email protected] 8 points 11 months ago

You can think of 1 as the "empty product" (or the "neutral element of multiplication" if you want to be fancy). 2^x means you have x factors of 2. If you have 0 factors, you have the "empty product"

[–] [email protected] 7 points 11 months ago

I like to think of it this way:
2^3 is the same as 2 x 2 x 2.
But you can arbitrarily multiply by as many 1s as you want because 1 has the identity property for multiplication.
So we can also write 2^3 as 2 x 2 x 2 x 1 x 1.
2^2 as 2 x 2 x 1 x 1.
2^1 as 2 x 1 x 1.
2^0 as 1 x 1 or just 1.

Multiplying a number by another number is the same as adding a number to itself that many times. And 0 is has the identity property for addition, so similarly:
2 x 3 = 2 + 2 + 2 + 0 + 0
2 x 2 = 2 + 2 + 0 + 0
2 x 1 = 2 + 0 + 0
2 x 0 = 0 + 0

[–] [email protected] 5 points 11 months ago

Its not the same. And theres proof, why.

[–] LordOfTheChia 4 points 11 months ago* (last edited 11 months ago)

In addition to the explanation others have mentioned, here it is in graph form. See the where the graph of 2^x intersects the y axis (when x=0):

https://people.richland.edu/james/lecture/m116/logs/exponential.html

This also has some additional verbal explanations:

http://scienceline.ucsb.edu/getkey.php?key=2626

The simplest way I think of it is by the properties of exponentials:

2^3 / 2^2 = (2 * 2 * 2) / (2 * 2) = 2 = 2^(3-2)

Dividing two exponentials with the same base (in this case 2) is the same as that same base (2) to the power of the difference between the exponent in the numerator minus the exponent in the denominator (3 and 2 in this case).

Now lets make both exponents the same:

2^3 / 2^3 = 8/8 = 1

2^3 / 2^3 = 2^(3-3) = 2^0 = 1

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[–] [email protected] 21 points 11 months ago (1 children)

Damn, that took me waaay too long to get...

Not my brightest moment... 😅

[–] hypertown 20 points 11 months ago

But when you finally get it

[–] affiliate 12 points 11 months ago (1 children)

for anyone curious, here's a "constructive" explanation of why a^0^ = 1. i'll also include a "constructive" explanation of why rational exponents are defined the way they are.

anyways, the equality a^0^ = 1 is a consequence of the relation

a^m+1^ = a^m^ • a.

to make things a bit simpler, let's say a=2. then we want to make sense of the formula

2^m+1^ = 2^m^ • 2

this makes a bit more sense when written out in words: it's saying that if we multiply 2 by itself m+1 times, that's the same as first multiplying 2 by itself m times, then multiplying that by 2. for example: 2^3^ = 2^2^ • 2, since these are just two different ways of writing 2 • 2 • 2.

setting 2^0^ is then what we have to do for the formula to make sense when m = 0. this is because the formula becomes

2^0+1^ = 2^0^ • 2^1^.

because 2^0+1^ = 2 and 2^1^ = 2, we can divide both sides by 2 and get 1 = 2^0^.

fractional exponents are admittedly more complicated, but here's a (more handwavey) explanation of them. they're basically a result of the formula

(a^m^)^n^ = a^m•n^

which is true when m and n are whole numbers. it's a bit more difficult to give a proper explanation as to why the above formula is true, but maybe an example would be more helpful anyways. if m=2 and n=3, it's basically saying

(a^2^)^3^ = (aa)^3^ = (aa) • (aa) • (aa) = a^2•3^.

it's worth noting that the general case (when m and n are any whole numbers) can be treated in the same way, it's just that the notation becomes clunkier and less transparent.

anyways, we want to define fractional exponents so that the formula

(a^r^)^s^ = a^r^ • a^s^

is true when r and s are fractional numbers. we can start out by defining the "simple" fractional exponents of the form a^1/n^, where n is a whole number. since n/n = 1, we're then forced to define a^1/n^ so that

a = a^1/n•n^ = (a^1/n^)^n^.

what does this mean? let's consider n = 2. then we have to define a^1/2^ so that (a^1/2^)^2^ = a. this means that a^1/2^ is the square root of a. similarly, this means that a^1/n^ is the n-th root of a.

how do we use this to define arbitrary fractional exponents? we again do it with the formula in mind! we can then just define

a^m/n^ = (a^1/n^)^m^.

the expression a^1/n^ makes sense because we've already defined it, and the expression (a^1/n^)^m^ makes sense because we've already defined what it means to take exponents by whole numbers. in words, this means that a^m/n^ is the n-th square root of a, multiplied by itself m times.

i think this kind of explanation can be helpful because they show why exponents are defined in certain ways: we're really just defining fractional exponents so that they behave the same way as whole number exponents. this makes it easier to remember the definitions, and it also makes it easier to work with them since you can in practice treat them in the "same way" you treat whole number exponents.

[–] [email protected] 5 points 11 months ago (2 children)

Ok, lemme say the line... NEEEEERRRRDD

(btw what's that math syntax, that doesn't look like latex equation mode)

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[–] takeda 5 points 11 months ago

Good luck trying that in two years.

[–] [email protected] 4 points 11 months ago

That happened

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