Message from @Deleted User

Discord ID: 427575596751519764


2018-02-20 01:39:50 UTC  

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

2018-02-20 01:43:46 UTC  

Thanks for the help!

2018-02-20 01:50:16 UTC  

@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!) -+...)

2018-02-20 02:33:10 UTC  

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

2018-02-20 05:38:33 UTC  

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

2018-02-20 05:39:15 UTC  

because the taylor series *is* the power series

2018-02-20 05:42:21 UTC  

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.

2018-02-20 15:13:46 UTC  

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

2018-02-20 16:18:30 UTC  

@JC17-OR You're welcome!

2018-03-05 22:38:10 UTC  

does anyone know anything about lognormal and weibull distributions?

2018-03-05 23:50:38 UTC  

<@&387091385075105804> ^^^

2018-03-25 21:04:05 UTC  

Need some help with a math problem @here

2018-03-25 21:05:55 UTC  

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?

2018-03-25 21:10:11 UTC  

Isn't that just 220 = 52 + 8x

2018-03-25 21:10:16 UTC  

Is the $52 a base pay?

2018-03-25 21:10:34 UTC  

If so @Jacob is correct

2018-03-25 21:10:55 UTC  

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

2018-03-25 21:11:54 UTC  

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

2018-03-25 21:12:23 UTC  

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

2018-03-25 21:12:42 UTC  

Solve for x

2018-03-25 21:12:46 UTC  

You solve for X but he got you started.

2018-03-25 21:13:40 UTC  

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

2018-03-25 21:14:11 UTC  

Okay that makes sense.

2018-03-25 21:14:25 UTC  

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

2018-03-25 21:15:43 UTC  

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.

2018-03-25 21:17:33 UTC  

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.

2018-03-25 21:18:02 UTC  

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

2018-03-25 22:00:06 UTC  

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

2018-03-27 02:38:38 UTC  

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

8x >or= 168

x >or= 168/8 = 21 deliveries

2018-03-27 02:38:47 UTC  

At least 21 deliveries in a day

2018-03-31 00:15:09 UTC  

>she
Nice try Schlomo

2018-03-31 00:18:21 UTC  
2018-03-31 00:18:57 UTC  

Making women deliver stuff...sad

2018-03-31 00:21:58 UTC  

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

2018-03-31 00:22:47 UTC  

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

2018-04-01 22:10:29 UTC  

https://cdn.discordapp.com/attachments/387060078433271808/430126835565723648/image.jpg

2018-04-01 22:10:52 UTC  

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

2018-04-01 22:11:19 UTC  

This section is on series solutions for linear equations

2018-04-01 23:55:34 UTC  

@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.

2018-04-02 00:59:55 UTC  

@ThisIsChris Thanks a ton!

2018-04-02 01:00:24 UTC