PI: Food Group or Math Concept? Pi Day Presentation

What is Pi? Not to be confused with “pie,” which is eaten for dessert, Pi is defined as the ratio of the circumference to the diameter of a circle Pi is usually denoted with this Greek symbol: π

Is Pi Dependent on the Size of the Circle? Nope! Pi is a constant, which means its value does not change. This means that the ratio of the circumference to the diameter of one circle is exactly the same as the ratio of the circumference to the diameter of any other circle.

What is the “Value” of Pi? Pi is an irrational number – its decimal digits do not repeat but “go on forever” Mathematicians estimate digits of pi to use it in real world settings. Pi is usually rounded off to about

Who Discovered Pi? In biblical times, some guessed that π was equal to 3, but that wasn’t very accurate. Archimedes was the first to theoretically approximate pi. He calculated that pi was “trapped” between 223 / 71 and 22 / 7, or roughly Today we use better approximations, most of which are derived by computers.

The Usefulness of Pi Pi is extremely useful for calculating the area and circumference of a circle: A = πr 2 and C = 2πr. Many disciplines of science use π in their equations (formulas) to describe the world. In fact, DNA, rainbows, the human eye, music, color, and ripples all have some natural roots in pi.

Hip to Be Square One interesting theorem related to pi deals with whether or not one can construct (with a compass and straight edge) a square with the same area as a given circle. That is, the red square on the left is equal in area to the small circle. This picture was not constructed using that method. Although such squares “exist,” it is not possible to construct them with a compass and straightedge because of the particular nature of pi.

The Big Five Pi helps link together the four other important numbers in math (e,i,0,1) in one equation: e πi +1=0 This equation is the result of the “Complex Exponential Function,” which is used in college mathematics

Pi Was Controversial ! Throughout history, people have been very passionate about math. In fact, some of the first mathematicians to consider the concept of “0” were executed for questioning the current system of thought (which at the time did not include the concept of “0”). An Indiana legislator tried to define pi as 3 but failed. The decision created an ugly yelling match between “traditionalists” and engineers.

Pi and the Arts A few have become so obsessed with the number π that they wrote poems about it: There once was a number Pi Very special like e and phi Circumference to d Is the ratio for me And it's not a multiple of I A 1998 movie about a code-cracker was named “Pi.”

Celebrate Pi Day, March 14th Yay!