Problem Writing Party 11 had lots of comments with active back and forth discussion. It's great that the community is helping each other improve posed problems, so that we can collate much better challenge quizzes.

Once again, I'm working on creating the challenge quizzes, and will update the following list ASAP. Some of you would also have received B-notifications that your problems were added to the quizzes over the course of the previous week. Keep it up! We value your submissions, and would love to feature more of them. Here are the quizzes that the Brilliant community helped create:

New Brilliant Challenge QuizzesAbsolute Value: Level 2, Level 3, Level 4

Linear Inequalities: Level 1, Level 2, Level 3

Radical Expressions: Level 1, Level 2, Level 3, Level 4

Uniform Circular Motion: Level 2, Level 4

New chapters

Operator Search: Level 2, Level 3, Level 4

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Let's kick off our **12th** Problem Writing Party!

## How it Works

The party starts right now (July 25th, 2016) and will last for the next two weeks. Throughout the two weeks, we will be focusing on writing awesome problems for the topics listed in quizzes that need your help on the **publish** page. We will be picking the best problems for each topic and they will be immortalized and formed into a challenge quiz. By participating, you will improve your presentation skills and learn how to write engaging problems that wow others!

The topics are:

Topic | Descriptions | Great Problems |

Partial Fractions | Is it true that \(\dfrac{4}{x^2-2^2} = \dfrac1{x-2} -\dfrac1{x+2}\)? | Level 2, 3, 4 |

Geometric Progressions | If I run 1 mile every day, and each day I run 10% more than the previous day, on which day onwards would I have run over 2 miles? | Level 1, 2, 3 |

Vieta's formula | If \(P,Q,R\) are roots to the equation \( x^3 + 2x^2 + x + 1 = 0\), then prove that \(P^3 + Q^3 + R^3 =-5\). | Level 3, 4, 5 |

Momentum | How do the pool balls move after they collide? | Level 2, 3 |

Taylor Series | Why is \(1 -\dfrac13 +\dfrac15 - \dfrac17 + \dfrac19 - \cdots = \dfrac\pi4\)? | Level 3, 4 |

Differentiation Rules | True or False? \( \dfrac d{dx} \left [ f(x) g(x) \right ] = \left [\dfrac d{dx} f(x) \right ] \left [\dfrac d{dx} g(x) \right ] \) | Level 2 |

Implicit Differentiation | What is the gradient of the curve \(x^2 +y^2 = 2\) when \(x= 1 \)? | Level 2 |

Abstract Data Types | How would you maintain a list to facilitate efficient deletion? | Level 3 |

## Use this note to

Ask questions about the party or brainstorming ideas from Brilliant staff.

Share links to great relevant problems.

Bounce your ideas off each other to help formulate the best problem you can.

If you're posting your problems, please keep it to one rooted comment (and I will be merging such comments from the same person). This helps us keep the page more orderly.

You can link to your own problems by using the markdown syntax of`[text](url link)`

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## Comments

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TopNewestI nominate @Jonas Katona's question for Taylor Series. – Pi Han Goh · 2 months ago

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– Jonas Katona · 2 months ago

Thank you for your support!! :) I will definitely post - and come up with some more problems - before this party ends. I totally agree with Rishabh: there are so many great topics for this party!Log in to reply

Here's my contribution: Rolling Rugby, Bizarre Hyperbola for Implicit Differentiation

Coyote VS Road Runner, Geometric Mystery for Geometric Progression

Evil 666 for Taylor Series

Power of Derivatives for Differentiation

The Roots Are Right There! for Vieta's formula

The Hidden Prime for partial fractions. – Worranat Pakornrat · 2 months ago

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– Pi Han Goh · 2 months ago

Wow your first question is a very creative setup. I tried ot solve it via geometry alone but I failed miserably. Looking forward to more questions!Log in to reply

– Worranat Pakornrat · 2 months ago

Thanks. I agree that things will get much easier with calculus. As a matter of fact, I was a bit surprised with the solution myself. 😉Log in to reply

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– Pi Han Goh · 2 months ago

Hmmm all the questions you posted here requires a lot of different math background, which end up making the question unnecessarily tedious. Do you have any straightforward questions?Log in to reply

New problem on Differentiation Rules:

https://brilliant.org/problems/chained/ – Denton Young · 1 month, 2 weeks ago

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May I add some new and old problems of mine? I think they're somehow overrated though :)

•for Taylor Series

•Vieta's 1

•Geometric Progression

•Geometric Progression 2

•Geometric Progression 3

•Geometric Progression 4

•Vieta's 2

•Vieta's 3 – Efren Medallo · 1 month, 3 weeks ago

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– Pi Han Goh · 1 month, 2 weeks ago

Woah! Your last question is great!!!! And I thought I want to find all the roots first =DLog in to reply

Another partial fraction question – Margaret Zheng · 1 month, 3 weeks ago

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– Pi Han Goh · 1 month, 3 weeks ago

Hmmmm, that doesn't look like partial fractions, but instead, it should be "long division of polynomials".Log in to reply

– Margaret Zheng · 1 month, 3 weeks ago

Okay... Then I'd love for it to be in "long division of polynomials". I will try to think of another one :)Log in to reply

partial fractions. – Pi Han Goh · 1 month, 3 weeks ago

Haha, no problem. In the meantime, you can read up the wiki page:Log in to reply

my question about partial fraction

and something is wrong with my correct answer choice... P.S. I am back from summer vacation to Brilliant! :) – Margaret Zheng · 1 month, 3 weeks ago

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Here are my contributions

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i challenge everybody and anybody to do this : " https://brilliant.org/problems/its-level-6-isnt-it/?ref_id=1244287 " let's see if you like that he he !! – Shubham Dhull · 1 month, 3 weeks ago

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Here is one for geometric progressions. – Aaron Tsai · 1 month, 4 weeks ago

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– Pi Han Goh · 1 month, 3 weeks ago

Nice question, I see that there are indeed many ways to solve this question. Not sure why it's in Level 4 though. HahahLog in to reply

– Shubham Dhull · 1 month, 3 weeks ago

you sure talk a lot ............. i will listen to your babbling after you have solved it . ha ha!!Log in to reply

– Shubham Dhull · 1 month, 3 weeks ago

were you able to solve that ques with even one of your 'methods' haHAHA!!!Log in to reply

Partial fraction challenge and Partial fraction challenge (2) – Tommy Li · 2 months ago

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– Pi Han Goh · 2 months ago

These are nice! Keep them cominggLog in to reply

GEOMETRIC PROGRESSION – Prince Loomba · 2 months ago

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VIETA'S FORMULA – Prince Loomba · 2 months ago

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– Pi Han Goh · 1 month, 4 weeks ago

This is nice. Got anymore of these?Log in to reply

– Prince Loomba · 1 month, 3 weeks ago

No I have posted problem on different logics except my set. Sorry!!Log in to reply

TAYLOR SERIES – Prince Loomba · 2 months ago

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All my entries will be here. I will try to write some more problems.

Taylor Series:

How's this related to trig?

I heard you liked infinite series, so here's an infinite series in an infinite series!

Infinite equation

Partial fractions:

Geometric progressions:

A geometric problem part II

Inspired infinite equation

Differentiation rules:

It's just derivative of sine, isn't it?

Don't confuse the sines

Implicit differentiation:

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– Pi Han Goh · 2 months ago

Love your partial fractions question. And I thought I need to use the quadratic formula. You got me there. Got more?Log in to reply

– Hobart Pao · 2 months ago

I'll have to think of them. Thanks!Log in to reply

I accept! Now, to come up with some new and creative problems... – Denton Young · 2 months ago

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– Pi Han Goh · 2 months ago

Remember to post them hereeeeeee! =DLog in to reply

momentum problem. – Denton Young · 1 month, 4 weeks ago

Okay! Here's a simpleLog in to reply

I have

twoBasic problems onG.P: 1 , 2oneproblem onImplicit Differentiation:1 – Sambhrant Sachan · 2 months agoLog in to reply

Geometric ProgressionsTaylor/Maclaurin SeriesPartial FractionsImplicit DifferentiationLog in to reply

Do post moreeeeee – Pi Han Goh · 2 months ago

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Is there any problem with the "Quiz that need help" link? It seems to direct to the list in the last party. – Worranat Pakornrat · 2 months ago

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– Pi Han Goh · 2 months ago

I think it's fixed now.Log in to reply

Here's one for Taylor Series (application). – Deeparaj Bhat · 2 months ago

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Sorry was busy. Will definitely contribute in next brilliant writing party – Anubhav Tyagi · 1 month, 2 weeks ago

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Here are sixth entries of problems:

Partial fractions 4, Partial fractions 5

Geometric progression 4, Geometric progression 5

Vieta's formula 7

Taylor series 5, Taylor series 6

Implicit differentiation 3 – Pi Han Goh · 1 month, 2 weeks ago

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Here are my fifth entries of problems:

Geometric progression 3

Vieta's formula 5, Vieta's formula 6

Implicit differentiation 2

Differentiation rules 2

Taylor series 4 – Pi Han Goh · 1 month, 2 weeks ago

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Here are my fourth entries of problems:

Vieta's formula 4

Differentiation Rules 1 – Pi Han Goh · 1 month, 3 weeks ago

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Here is my third entry of problems:

Partial fractions 2, Partial fractions 3

Geometric progressions 2

Vieta's formula 2, Vieta's formula 3

Taylor series 1, Taylor series 2 – Pi Han Goh · 2 months ago

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Here is my second entry of problems:

Vieta's formula 1

Implicit Differentiation 1 – Pi Han Goh · 2 months ago

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Here is my first entry of problems:

Partial Fractions 1

Geometric Progressions 1. – Pi Han Goh · 2 months ago

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