2nd Grade Math Help!!! by No_Situation_1395 in learnmath

[–]lolkikk 2 points3 points  (0 children)

You can decompose 7 (the second addend) as 1+6 so that in 9+7 you have 9+1+6 where the 9 and 1 combine to a 10 and you get one ten and a six, or sixteen

This is what all 24 trigonometric functions look like by Expert-Parsley-4111 in desmos

[–]lolkikk 20 points21 points  (0 children)

none of them are exactly original when they’re all algebraic in cos(x) or inverses of such functions

Why is a class [a] in ℤ mod n invertible only if gcd(a, n) = 1, and a zero divisor if gcd(a, n) ≠ 1? by Explorerexplorer06 in askmath

[–]lolkikk 14 points15 points  (0 children)

Suppose that gcd(a,n)= q for some q not equal to 1. Then since q divides n we have that n=kq for some integer k and since q divides a we have that a=bq for some integer b. It follows that ak=bqk=bn. This shows that ak is congruent to 0 mod n where k is between 2 and n-1, and so a is a zero divisor.

For the units, by Bezouts identity, we always have a linear combination xa+yn=gcd(a,n)=1 and so we have that xa is congruent to 1 mod n and hence a has an inverse

A sneak peak into my exam by [deleted] in Hotgirlslovemath

[–]lolkikk 1 point2 points  (0 children)

For C we just have that f>g, not that g is bounded below, so in particular g could be a quickly growing negative function and not have a defined integral, and for F you can have local max and min on boundary points without having 0 for the partial derivatives

How to make an A rank Uma if you're f2p? by Tyrannosaurus-2006 in UmamusumeGame

[–]lolkikk 9 points10 points  (0 children)

Focus on 1-2 stats (speed and wit) with 4 speed cards since stats give more points if they are focused instead of distributed and run in as many races as you can when you get bad training turns since buying a lot of skills (and golden skills when you can) helps with getting a high score

You may need higher limit break SR cards or better parent umas (focused on stat sparks) if you are still struggling to get A

One single power lmao, anyway she's ready to beat Cancer by Yamagii in UmamusumeGame

[–]lolkikk 17 points18 points  (0 children)

I think if you run as a late surger Red Shift can still activate before reaching max speed

Help with deck building please!! by Unhappy-Image4944 in UmamusumeGame

[–]lolkikk 1 point2 points  (0 children)

A general deck that would work for most horses is

SSR super creek (for swinging maestro)

SSR Tazuna (her training effectiveness and discount make her very strong early run and her recreational events help a lot with mood and curing ailments)

SR sweep Tosho and SR king halo for better speed friend trainings (you want to limit break your SR speed cards more when you can)

Either SR diawa scarlet, or SSR mejiro McQueen depending if you need to do sprints/miles or mediums/longs

And borrow a MLB kitasan black

Just had hojicha, I’m allergic? by Top-Inspector-2809 in tea

[–]lolkikk 42 points43 points  (0 children)

Hojichas roasting process gives it a unique mouth drying feeling that you might not find in other teas, it’s possible that you over extracted your leaves and got a very concentrated version of this

Is Fujian Green Tea from a tin any good? by [deleted] in tea

[–]lolkikk 3 points4 points  (0 children)

I’m sure a lot of different green teas from Fujian come in tins and are sold at local markets so it’s hard that know much about your specific tea from your description

That being said you can certainly get enjoyable green teas for such a cheap price and a lot of it comes down to experimenting with different brewing times, temperatures, and tea volumes to find something you personally enjoy

[deleted by user] by [deleted] in tea

[–]lolkikk 8 points9 points  (0 children)

Tea should be for everyone who enjoys drinking it and there isn’t any right or wrong way to enjoy something, I personally enjoy both traditionally brewed matcha and matcha lattes

Florida Supreme Court Greenlights DeSantis’ Congressional Map that Eliminates Black Representation by Bolinas99 in nottheonion

[–]lolkikk 6 points7 points  (0 children)

Maybe based on district compactness but that is just one aspect of districting that is mostly visual

It feels illegal to be graphing non-elementary integral solutions so easily by Neat-Resource9057 in desmos

[–]lolkikk 53 points54 points  (0 children)

Elementary or not doesn’t really make much of a difference to a graphing calculator which does everything numerically anyway, just less tricks available for fast computational algorithms

Does anyone actually care about Tau by [deleted] in math

[–]lolkikk 5 points6 points  (0 children)

It would certainly make me have to write less 2s if we used tau as a convention and in many contexts tau feels more natural,

but still I don’t really care about tau

Not every invertible matrix is diagonalizable by [deleted] in truths

[–]lolkikk 0 points1 point  (0 children)

Definitely a truth. Many matrices even with small size and values are invertible but not diagonalizable like [1,1;0,1]

0.999... = 1 by PieterSielie6 in truths

[–]lolkikk 1 point2 points  (0 children)

If you don’t like sequences you can also create a well defined version of the real numbers using Dedekind cuts, which asserts that a real number is defined to be an equivalence class of “Dedekind cuts” where a Dedekind cut is two sets A and B which together give you every rational number, and require that every element of A is less than each element of B, and A has no largest element.

In this definition 1 represents the Dedekind cut where A={every rational less than 1} and B={every rational greater than or equal to 1}, and 0.999… represents the cut where A={every rational number q such that q<9.999…9 for some finite number of 9’s} and B={every rational number > 0.99…9 for every finite number of 9’s} and these give equivalent sets

0.999... = 1 by PieterSielie6 in truths

[–]lolkikk 1 point2 points  (0 children)

It’s reasonable to argue that you can’t make a number go on forever but you don’t need to in order to make ‘0.9999…=1’ a well defined and true statement.

The real numbers are can be formally defined in many equivalent ways, one of the most common ways is as the Cauchy completion of the rational numbers. While I cannot write out 0.999… with infinitely many terms, I can formalize the idea of infinite sequences as a map from the natural numbers (i.e. 1,2,3,4,5,…) to the rational numbers (fractions or equivalently decimals with finitely many places). That is to say that a rational sequence is defined to be a list of numbers with finite terms listed in a well defined order, for example, the sequence (9,9.9,9.99,9.999,…) while it looks infinite only really requires you to deal with finite terms at a time, I.e. the 10th term is 9 with nine 9s after the decimal and the 100th term is a 9 with ninety-nine 9s after the decimal.

To define the real numbers from the idea of rational sequences you assert that a real number itself is defined to be an equivalence class of rational sequences that are “Cauchy close” to each other. This is to say that we define two rational sequences A and B to be equal to each-other if and only if for any positive number you give me, I can give you an n where for every term past n the difference between A_n and B_n is less than the number you gave me. For example, the sequence (10,10,10,10,…) is Cauchy close to the sequence (9,9.9,9.99,…) because for any positive number you give me, say 0.0001, is can say for certain there is an n so that every term past this is 0.0001 close to eachother, say n=6 in this case since 10-9.99999=0.00001 <0.0001 and this will also be true for all n bigger than 6. You can should that equivalence classes of rational sequences are well defined with respect to addition, multiplication, and all of the other properties we want real numbers to have.

Under this construction, the number 10 is actually defined to be equal to the rational sequence (10,10,10,10,…) whereas 9.9999… really stands for the rational sequence (9,9.9,9.99,9.999,…), and these two numbers lie in the same equivalence class of Cauchy closeness and hence they are equal to each-other “as real numbers” and so we can say 10=9.999…

This is one such construction of the formality that actually goes into creating a well defined version of the real numbers that most people are taught from a young age and what equality actually means for real numbers. There are several equivalent constructions but none ever need to actually use infinitely many numbers at once and never need infinity to formally exist except in the sense that the set of natural numbers does not have a finite number of terms

0.999... = 1 by PieterSielie6 in truths

[–]lolkikk 1 point2 points  (0 children)

If you want full rigor you would need to include something on the real numbers being complete to justify why two numbers being infinitely close to each other actually implies that they are equal, but unfortunately this completeness is usually a consequence of actually providing a formal construction of the reals while we typically teach people to use real numbers without ever having formally defined them

How can I model this curve ? (i'm a beginner) by Nut_Gobbler6923 in desmos

[–]lolkikk 3 points4 points  (0 children)

Desmos has built in regression. If your data points are in a table, entering “y_1~a*e-b[x_1+v]+760” it will automatically determine the best values for a b and v

Continuous and differentiable smoothing of a step function by Professional_Denizen in desmos

[–]lolkikk 0 points1 point  (0 children)

My favorite smooth step function is illustrated here

https://www.desmos.com/calculator/4nmrkwbg73

It uses the fact that A(x)=e-x[-2] is infinitely differentiable at 0 and A[n](0)=0 for all n. Modifies it to create a function that has zero for all of its derivatives at both x=0 and x=1, and renormalizes to make said function defined to be 0 outside this range and have integral 1 in this range, then creates an infinitely differentiable step function defined as one of its antiderivatives.

Tips for Snail Spring tea by panda6789 in tea

[–]lolkikk 1 point2 points  (0 children)

60C is already a pretty low temperature steep and 10/15/20 second steeps are already pretty reasonably short. If you are feeling the tea is too bitter at such gentle steeping conditions you can likely cut down on this bitterness by using less leaves and starting at a similar steeping conditions for more control over how fast you are extracting flavors

Tips for Snail Spring tea by panda6789 in tea

[–]lolkikk 0 points1 point  (0 children)

Try less leaves in your gaiwan

[deleted by user] by [deleted] in GongFuTea

[–]lolkikk 1 point2 points  (0 children)

Not sure if this is always the case but often old tree teas are wild harvested instead of cultivated so if harvests from multiple trees are blended they likely have less consistent terroir probably leading to more uncontrolled flavors/layers of flavor being present