This sounds a lot like mastering physics

Whenever you get it wrong

Yeah haha and I am not a scientific person

I'm majoring in media production.

Bring it up with whoever you can. If you actually understand the concepts you shouldn’t be graded down

I might. My instructor is Asian with a broken accent of course. Yeah I've demonstrated that I understand how to do the concepts

Send screenshots or show photos of your work and really nail them down. Say “show me what’s wrong or the programming is bad”

If you have white TAs or even TAs that speak English use them

What's a TA?

Oh nvm

LOL

Sorry duh

Oh I thought it was joke, haha. You’re good

I got my STEM degree on the west coast so I know a thing or two about Asian “teachers”

This guy isn't even a "teacher" he just sits at his desk while we come into class to work on a $100 computer program

Straight up caught a Chinese born TA giving answers to a Chinese born student before the midterm in office hours

Wow

The educational system is welfare for people that want to pretend they have a job

That’s why it’s occupied by women at the lower levels

That and the fact that it is about nurturing children until about 6th or 7th grade

Yeah pretty much. At the lower level it's not too bad. But after that I can agree. I'm gonna have to see if there's any white TAs around lol

Was there a guy in here offering Calculus help

I may an hero if I have to listen to my 1st Gen immigrant instructor try to explain Calculus concepts without teaching how to solve problems.

@Corey

@Deleted User there are a few of us who can help with calculus. Personally I used to teach it for many years. What kind of problems are you trying to solve?

We started with limits and are moving into derivatives and tangent lines. It just seems like the instructor is getting high on his own supply of math knowledge and not teaching us a clear cut way to solve the problems.

He also doesn’t explain any rule he uses especially with algebraic manipulation which makes it difficult to follow.

I’m having trouble recognizing the problems and what rule to apply to find solutions

read the book along with the class

also, talk to the dept head maybe

Yeah right now I’m fairly reliant on the YouTube.

@Deleted User feel free to regularly post photos of problems you are working on

Sure when I hit a roadblock I’ll post a pic

@Deleted User Professor Leonard on YouTube has great videos for calc concepts. Also feel free to post pictures of problems if you want to.

this Professor Leonard guy is swole af

Does anyone here know Matlab? I’m taking a Matlab class and am super confused

@Sam Southern - TN I know *some* Matlab, what's up?

Driving rn, I’ll send what I’m working on in like 10. It’s basic (apparently lol), but I am not good at the cyber

Gen Z not being good at cyber hahah not living up to my gen I know

@Sam Southern - TN sounds good, post it when you can

1. Write a function (I'm calling it v) that takes in two scalars (a and b) spits out a vector (v) that is a row vector of the length b with the terms being the first a powers of b

So I tried to do someting like this:
function v = hw1_problem5(a,b)
b = length(v);
v = a.^b;
end

so that the function length would track with b and the vector would be that length

and the vector itself would use vector exponent rule of .^ to raise each to the correct power

but it's only giving me the first output instead of all of the outputs

for example, when I input hw1_problem5(2,3), it should output a row vector containing the first 3 powers of 2

so [2 4 8]

but it only gives [2]

so it's not accepting my length argument somehow

there's another one after that that involves zeroing out part of an array in certain locations, but I'll take any help i can get

shit is so confusing to me

@ThisIsChris let me know if that doesn't make sense

if any other <@&387091385075105804> know how to matlab, I would greatly appreciate the help!

@Sam Southern - TN the second line, `b = length(v);` is changing the value of b

how do I set the length of the vector to b?

@Sam Southern - TN so first I would make a vector of 1..b, I'll call it powers, s

so
`powers = 1:b`

then

`v = a.^b`

now it's giving me the last one instead of the first one as the output

so [8]

instead of [2]

but not [2 4 8]

hmm I see, I'm at work now will have to check this out in a little while (unless someone else steps in 🙂 )

thanks for trying though, I do appreciate it

@Sam Southern - TN this works

The trick I had to remember was that a function that accepts scaler, if you plug in a vector, will return you a vector with the function applied to each entry

that, and making the vector 1...b is `1:b`

@ThisIsChris thank you, that works!

just got back from work, happy to see this finally work hahah

@Sam Southern - TN You're weclome! 😄

Whoever recommended Professor Leonard. Probably the best videos I've found for this. Much appreciated

@Deleted User that was @JC17-OR

@Deleted User My pleasure

I was wondering if someone could help me with a problem for my financial mathematics class?

<@&387091385075105804>

@Tycho Brahe @Zyzz you guys too may have some insight for @Deleted User ?

I'll go ahead and post a screenshot of the problem so people could see if they would be able to help.

@Deleted User What's the question? If you drop it here then when someone who can help comes on they can work on it

yeah perfect

Here are my notes. The example is supposed to align with how to do the problem, I just can’t seem to get the right answer.

Let me know if my notes can't be read.

I'm going to get some rest for tonight, but if anyone would still want to look at it and give me some guidance, I would greatly appreciate it. 😃

First, find future value:
FV = Principle\*(1 + rate\*time)
FV = 875*(1 + .1025 * 2)
FV = 1054.375

Then in one year there will be one year on the note left, and the bank is going to discount that at a 17.5% rate, so the discounted value the bank pays satisfies:
FV = DV * (1 + .175 * 1)

Plugging in the value for FV from before:
1054.375 = DV * (1.175)

Dividing both sides by 1.175 we get:

DV = 897.3404255319 = 897.34

So the holder of the note went from 875 to 897.34 in one year, so he has his own future value calculation he can plug values into:
897.34 = 875\*(1 + rate_for_holder \* 1)

dividing both sides by 875 you get:

1.0255314286 = 1 + rate_for_holder
so rate_for_holder = 0.0255314286... ~~ 0.026
so the rate for the holder is 2.6%

@Deleted User

Thank you! @ThisIsChris I think I understand it much better now.

My pleasure! @Deleted User

Hey everyone I need some math help. I'm trying to do the final problem and I can't figure it out.

The best I've come up with is that the 2S-S argument only works for 2S -S, if you go above 2S-S to say 3S-2S, then it diverges to infinity. Also the r-value of 2 cannot be used in the geometric series sum equation as it is not between -1&1.

Any help is super appreciated.

If you talk about 3S you're just bringing more things in that you don't need.

when you do 2S-S you should have the same number of elements on both sides, or at least write it in the form of a sum

If you subtract these two sums, you should subtract the first from the first, the second from the second, etc.

So what you're saying is that the proof relies on ignoring standard rules of subtraction with equal terms.

It makes the assumption that you can subtract the 2+4+8+... of the S from the 2S while leaving the 1 untouched which negates the idea of infinity because it is adding terms to S that it is not adding to 2S to leave the 1 untouched.

When they subtract terms in the example, they're kind of cherry picking which to subtract first. It's not written in a strict mathematical way, so it flies under the radar. Imagine you said s = 1+1+1+..... You could say s -s = (1+1+...) -(1+....) = 1, yet s-s should be 0.

So you can point out that it's not written in a very precise way.

That makes sense. The proof isn't valid because it relies on a specific way to subtract the sums which doesn't follow mathematical rules.

Do I have that right?

@JC17-OR correct, the proof relies on the sum being the same if you are allowed to rearrange terms, but you are not guaranteed to be able to do that if the series is not absolutely convergent

Or you could say that they are using a different number of terms in each series in order to get the result that did. Which means that they didn't acttually double s, since s and 2s should have the same number of terms. If both series have the same number of terms, they end up with 2s-s = 2^N - 1, where N is the number of terms.

@JC17-OR You can also just prove that the series diverges just by making the terms rigorous:
Define S_n = sum i from 0..n of i^2
Then S = lim n->inf S_n

S_n you can compute explicitly, because it is a finite sum you can do:
2\*S_n - S_n = 2\*(n+1) - 1
i.e. S_n = 2^(n+1) - 1

so S = lim n-> inf 2^(n+1) - 1 = inf

That makes alot of sense.

Any thoughts on the 4th problem. My teacher hasn't been much help and my classmates are as lost as I am.

I figured I could take out the 1/sqrt(2pi) and have the integral e^(-x^2/2), integrate that and do the Taylor series that way, but that didn't work out.

@JC17-OR Unforunately I have to eat dinner now, but here is the lead, the derivative of F is f(x), but you know the taylor series for f(x), just take the taylor series for e^x and plug in (-x^2) where x is

So the taylor series for F is just the antiderivative of the taylor series for e^x * 1/sqrt(2pi) with (-x^2) plugged into x

Thanks for the help!

@JC17-OR You're welcome! Here's the full demonstration in case you want it:
F is the antiderivative of f so first find the taylor series of f:
f(x) = (1/sqrt(2pi)) * e^(-x^2)
taylor series for e^y is:
e^y = 1 + y + y^2/2 + y^3/3! + y^4/4! +...
plug in y=-x^2
e^(-x^2) = 1 - x^2 + x^4/2 - x^6/3! + y^8/4! -+...
so f(x) = (1/sqrt(2pi) * (1 - x^2 + x^4/2 - x^6/3! + y^8/4! -+...)
so F(x) = (1/sqrt(2pi)) \* (x - x^3/3 + x^5/10 - x^7/(7\*3!) + x^9/(9\*4!) -+...)

Does anybody have an idea for the power series from the given Taylor series?

@JC17-OR do you mean the radius of convergence?

because the taylor series *is* the power series

Anyway I forgot to mention the radius of convergence is infinity, because f(x) is a probability density function, so the integral of f(x) for x from -infinity to infinity is 1.

I'm dumb that's what I meant to say. I figured it out, thanks for all your help.

@JC17-OR You're welcome!

does anyone know anything about lognormal and weibull distributions?

<@&387091385075105804> ^^^

Need some help with a math problem @here

I have to solve a linear inequality problem:
A delivery driver makes $52 each day that she works and makes approx. $8 in tips for each delivery. If she wants to make $220 in one day at least how many deliveries does she need to make?

Isn't that just 220 = 52 + 8x

Is the $52 a base pay?

If so @Jacob is correct

Is is not (220 - 52) \ 8 = x

Oh jacob beat me to it. Jacob wrote the more proper expression tbh.

Do you solve for x or just leave it as that expression?

Solve for x

You solve for X but he got you started.

Since you get "approximately 8 dollars per tip' the answer will be "about" (whatever x is ) deliveries

Okay that makes sense.

Thanks. Your goy here can't do maths to save himself

Everyone has strengths and weaknesses. This one's pretty basic though. I used Kahn Academy alot in college when I had a foreign teacher who didn't explain things in an articulate manner.

I'm in a learning support math class since my ACT score wasn't high enough to be eligible for me to enroll in the primary math course required for my major.

So I have to take this class and then college algebra class and then hopefully I'm done

Kahn's really good if you prefer to learn with videos

52(base pay) + 8x(tips per delivery >or= to 220

8x >or= 168

x >or= 168/8 = 21 deliveries

At least 21 deliveries in a day

>she
Nice try Schlomo

@Freiheit - CA ?

Making women deliver stuff...sad

220-52=168
168/8=21
21 deliveries

She must live in Texas where tipped pay is $.38/hr or something

Anyone who has taken a class in Differential Equations, could you confirm if the answer in green makes sense?

This section is on series solutions for linear equations

@ButMomShesA300YearOldLoliVampire yes the way you solved it up to the green circle is correct. Now the question asks for you to find two linearly independent solutions. In the green circle you see that after you specify `C_0` and `C_1` that all the other coefficients of a solution are determined. So for one solution choose `C_0 = 1` and `C_1 = 0`, and for the other solution choose `C_0 = 0` and `C_1 = 1`. These solutions are linearly independent since no scalar multiple times the `C_0` and `C_1` of one solution will ever give you the `C_0` and `C_1` of the other solution.

@ThisIsChris Thanks a ton!

@ButMomShesA300YearOldLoliVampire you're welcome!

@Warren H Better to just post your question.

Working on graphing linear equations in two variables (x and y).

And the line I have to graph is 5y=9

I put it in a graphing calculator and came back with a straight line (0,0) which is incorrect as the problem is asking for two coordinates for x and y

If theres no x in the equation it will be a straight line. Y = 9/5

@Warren H

@Warren H To add to @Deleted User 's response, you can rewrite `y = 9/5` as `y = 0x + 9/5`. Remember line formula is `y = (slope of line)x + (y-intercept)`. So for @Deleted User 's formula you have a slope of zero (i.e. a flat line) and a y-intercept of 9/5.

So the answer I came back with is 0, 1.8

But the computer program I have to do my homework on requires me to answer the x coordinate and it will not accept 0. Very weird

@ThisIsChris @ChillS

@Warren H hmm, how exactly is the question phrased? Do you have a screenshot?

Oh you need to enter something for B as well, any other point on the line will do. (They say enter two points because two points determine a straight line). You can enter any other point from the line, for example (1, 1.8)

Ohhh okay. That seemed to have worked. Is this the case whenever there is a straight line?

@Warren H yep!

This program drives me nuts

I just got another answer wrong for writing it in decimal numbers but it was counted as wrong because the answer was in fractions. Did the math calculation, and the fractions converted into the decimal coordinates that I entered.

Do you have a screenshot? I wonder if there's something specific in their question phrasing that indicates they want fractions instead of decimals.

It did not. It just said "Find the y-intercept and x-intercept of the following linear equation."

That's so weird, so for the y-intercept, they rejected 7.5 as the y-intercept? That's so weird because *they* give you the equation in decimal!

oh woops sorry that was the next problem

the one they flagged wrong was the coordinate points -4.8 and -0.375

they said those were incorrect and that the right answer was -24/5 and -3/8 which are the exact same numbers

@Warren H do you get points off for that? might want to bring it up with your professor in that case

Yes I did. I will for sure. If this was on a test and graded in that way I would have gotten the problem wrong

Hi. New to the server. If anyone needs help with any kind of research, I'm your goy. I have a lot of experience in it and I even enjoy it oddly enough. This extends out to school essays, work related, or even anything out of general curiosity. Any subject as long as I don't need a degree to grasp the basic concept. I can write you(within reason and with digression) any paper/article, and other kinds of research assignments. I also excel at photo shop. Advice and suggestions are free. Real work is cheap. DM me if you are interested.

Does anyone have any protips or suggestions on how to cultivate a better habit of doing homework/getting schoolwork done outside of class? All through normal school I was in the category of kids who didn't need to study and could get through homework during school hours without much difficulty, but now that I'm in college my grades are suffering because I don't have the habit/mindset of doing homework/studying outside of class. Anybody have experience with overcoming this?

@Gaius Mucius Scaevola Wake up early. 5:30-6. Go for a run. Then block 1-2 hours for homework. If it isn't done first thing, there won't be motivation left at the end of the day.

wake up, go for a run/exercise, breakfast, homework

I think I can do that to catch up on all the work i'm behind on this semester

I'm not really a classroom/lecture learner, I learn by doing which is why i went to trade school

all the lab/trade classes I do much better at

it's the classes with lectures and homework i struggle in

has anyone read "Nations and Nationalism" by Ernest Gellner

Not all of it, but some. @johnnyc

Why?

gotta do a book review on it

ive read a good amount but i dont have time to finish and was struggling to figure out what i should write

How about a defense or refutation of the main idea. Which, I believe, is something along the lines of 'nationalism is a bureaucratically enforced method of creating a homogeneous population through state or industry created organizations.'

Nationalism, as being in opposition to localism or tribalism.

Well, not exactly in opposition. As the 'group' becomes a larger entity, it becomes more difficult to maintain a truly homogeneous culture. Ergo, it becomes important for state-created organizations to synthesize naturally-formed local cultures to form a 'baseline median.'

It's like how 'Germany' is really a combination of more local groups from Prussia, Swabia, Bavaria, ect.

gotcha, yeah the main things in the paper are supposed to be identifying the main argument/s and evaluating its persuasiveness

i was having some trouble narrowing down what the actual main argument was

"nationalism is an inescapable consequence of modernity" i think is some of it

idk whether to write about that or maybe include his definition of nationalism as wellmaybe

Yes. That's exactly right. But it must be noted that he defines nationalism as to mean the combination of local groups to form a median. You should include both points because they support each other.

Because by 'modernity' he means the breakup of agricultural society in favor of industrialization.

One is just the outflow of the other.

okay nice that helps clear it up thank you!

Although, as a counter-argument, you could make the claim that it isn't *really* industrialization that is the main cause.

*cause of nationalism

true i was thinking that aswell

Interesting. What example are you going to use?

im not sure yet, kind of just gathering my thoughts and re-reading some parts right now

Ok! Good luck.

thank you!

Is anybody in here a Calculus wiz?

@GDoctor taught it for many years, I can probably help

What are you looking at?

@ThisIsChris I'm In calculus 1 right now and there are no prerequisites however, it assumes a high school background in pre-calculus. The problem is that high school was over 10 years ago for me and I didn't do well in it. I'm going to post a scan of my latest homework and would like to know how to solve the problems in layman's terms. The scientific calculator I have is a TI-84 Plus.

Here's my current homework. It's due September 5th.

@GDoctor here is 1a and 1b

@ThisIsChris Thank you very much! I'm signed up for tutoring at my school so hopefully I'll catch up and remember how to do this stuff in my head. Tests account for 85% of my final grade.

<@&435155896780324864> Can someone tell me why I'm getting a null pointer exception in Java?

?

how do you paste code?

```java
import java.lang.*;
```

\`\`\`java
code
\`\`\`

```java
public boolean contains(Object o) {
for (int i = 0; i < size; i++) {
if (o == null && get(i).data == null) {
return true;
}
else if (get(i).data.equals(o)) {
return true;
}
}
return false;
}
```

```java
public ListNode get(int index) throws IndexOutOfBoundsException{
ListNode cur = head;
for (int i = 0; i < index; i++) {
if (i == index) {
return get(i);
}
cur = cur.next;
}
return null;
}
```

pls no bully I haven't taken Java in two years and now I have to relearn everything

get(i).equals

make the first && an ||

but I'm checking to see if they're both null

but the elseif

o could be null

```java
// Returns true if this list contains the specified element o.
// More formally, returns true if and only if this list contains at least one element e
// such that (o==null ? e==null : o.equals(e)).
// Note: you have to handle the case where a list node stores null data element.
```

if o is not null you will move to the else if

and get(i).data could be null

do this

Object.equals(get(i).data, o)

in the else if

handles nulls

says that the method is not applicable for arguments

Objects.equals

ah

not Object

I still get a null pointer exception from the if statement

this is what is being tested btw

```java
public static void testContains() { //passed test
init();
System.out.println("----------------testContains()------");
System.out.println(list0.contains(null));
System.out.println(list2.contains("1:Good"));
System.out.println(list2.contains("6:Tony"));
System.out.println(list2.contains("notexist"));
System.out.println(list2.contains(""));
System.out.println(list2.contains(null));
System.out.println(list3.contains("notexist"));
System.out.println(list3.contains(null));
drawLine();
}
```

that is from the tester class, not the same class

break when cur is null

it shouldn't break though

it should theoretically be able to find objects with data set to null

cur.next

cur is never null?

recursively