Pi | Recreational mathematics

Six nines in pi

A sequence of six consecutive nines occurs in the decimal representation of the number pi (π), starting at the 762nd decimal place. It has become famous because of the mathematical coincidence and because of the idea that one could memorize the digits of π up to that point, which seems to suggest that π is rational. The earliest known mention of this idea occurs in Douglas Hofstadter's 1985 book Metamagical Themas, where Hofstadter states I myself once learned 380 digits of π, when I was a crazy high-school kid. My never-attained ambition was to reach the spot, 762 digits out in the decimal expansion, where it goes "999999", so that I could recite it out loud, come to those six 9's, and then impishly say, "and so on!" This sequence of six nines is sometimes called the "Feynman point", after physicist Richard Feynman, who allegedly stated this same idea in a lecture. It is not clear when, or even if, Feynman made such a statement, however; it is not mentioned in published biographies or in his autobiographies, and is unknown to his biographer, James Gleick. (Wikipedia).

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Pi - Sixty Symbols

It's more of a maths symbol, but crucial to physics too... So by popular demand, we've had a look at pi (but in Professor Eaves' unique way). More at http://www.sixtysymbols.com/

From playlist From Sixty Symbols

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MegaFavNumbers: Plus One Primes, 154,641,337, and 62,784,382,823

My entry in the #MegaFavNumbers series looks at a particularly striking example of a very specific family of primes -- and how it connects to what digits can be the final digit of primes in different bases.

From playlist MegaFavNumbers

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A random approximation for Pi (pi day short)

In this short, we randomly sample 5000 pairs of positive integers and use the pairs to plot points in the plane. If a pair is relatively prime, we shade the dot red; otherwise we shade the dot blue. The theory behind this process says that roughly 6/pi*pi of the dots will be red. So we can

From playlist Pi

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Ex 2: Determine Factors of a Number

This is the second of three videos that provides examples of how to determine the factors of a number using a numbers prime factors. Search Video Library at http://www.mathispower4u.wordpress.com

From playlist Factors and Prime Factorization

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Examples: Addition of Decimals

This video provides 4 examples of adding decimals with different place values. Complete video list: http://www.mathispower4u.com

From playlist Adding and Subtracting Decimals

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A Five Pi Diagram (pi day short)

In this short, we give five different formulas for pi (or related constants) using only a single diagram consisting of a 3x2 rectangle and a triangle inside. Using the fact that the tangent of an angle is the ratio of the opposite and adjacent sides of an angle (and you can get the angle u

From playlist Trigonometry

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What is the Meaning of Pi

This tutorial explains the meaning of Pi. Join this channel to get access to perks: https://www.youtube.com/channel/UCn2SbZWi4yTkmPUj5wnbfoA/join :)

From playlist All about Circles

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Calculus AB Homework 6.2 Riemann and Trapezoidal Sums

Download Packet: https://goo.gl/xeg85Y ================================= AP Calculus AB / IB Math SL Unit 6: Integration Lesson 2: Riemann and Trapezoidal Sums =================================

From playlist AP Calculus AB

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A-Level Maths Edexcel Core 3 Past Paper Questions: Ch7 Rcos(theta+alpha) method

Powered by https://www.numerise.com/ All past papper Edexcel Core 3 questions on Rcostheta plus alpha method. www.hegartymaths.com http://www.hegartymaths.com/

From playlist Core 3: Edexcel A-Level Maths Full Course

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Pi (π) Day Listening Party Featuring John Sims + “Round” Table

Pi (π) Day “Round” Table + Listening Party 1:15 p.m. - 2:00 p.m. No matter how you slice it, you won’t want to miss Pi Day—we’ll be celebrating differently this year, but you can still join the party for this irrational and transcendent figure. Tune in for our panel of pi enthusiasts dish

From playlist Pi Day | Exploratorium

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Ex: Find the Area of a Inner Loop of a Limacon (Area Bounded by Polar Curve)

The video explains how to find the area of the inner loop of a limacon. Find the area bounded by a polar curve. Site: http://mathispower4u.com

From playlist Derivatives and Integrals with Polar Equations

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Integration (10) - The Trapezium Rule (C4 Maths A-Level Edexcel)

Powered by https://www.numerise.com/ The trapezium rule www.hegartymaths.com http://www.hegartymaths.com/

From playlist Integration Techniques Core 4 Maths A-Level

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MegaFavNumbers 262537412680768000

This video is a contribution to the #MegaFavNumbers project, which seems to have overlooked the number 262537412680768000 This number turns up because e to the power of pi times the square root of 163 is about 262537412680768743.99999999999925... with a spectacular sequence of 9s after t

From playlist Math talks

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Live Stream #126.2: Happy Pi Day - Part 2

Pi Day continues! 🎥 Live Stream Part 1: https://youtu.be/BOk4Dl-gw14 7:37 - Coding Challenge: Book of Pi 1:00:09 - Coding Challenge: Book of Pi Continued 🔗 Sponsor me for a charity half marathon!: https://crowdrise.com/o/en/campaign/the-lower-eastside-girls-club-nyc-half-2018/shiffman 🔗

From playlist Live Stream Archive

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Crash Course Trigonometry 12: Solving Trigonometric Equations

In this video, I work through several examples of solving trigonometric equations. Specifically, I explain how to solve equations of the form "trigonometric function of x equals a value." I explain how to use "special" angles and reference angles, as well as calculator methods.

From playlist Crash Course Trigonometry

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Rate Application: Determine Calories of a Large Pizza using Area

This video explains how to use a rate to determine the number of calories in a large pizza given the calories of a small pizza. http://mathispower4u.com

From playlist Ratios and Rates

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Finding Area In Polar Coordinates

This Calculus 2 video tutorial explains how to find the area of a polar curve in polar coordinates. It provides resources on how to graph a polar equation and how to find the area of the shaded region. It contains plenty of examples and practice problems on how to find the area of one lo

From playlist New Calculus Video Playlist

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03 Placing numbers on a number line #38

In this video we place rational and irrational numbers on the number line

From playlist Skill 13 Attempt 2

Related pages

0.999... | Decimal | Heegner number | Rational number | Repdigit | Pi | Richard Feynman | Conjecture | Normal number | Mathematical coincidence