1 / 9

By Tracy Hanzal

Pi. By Tracy Hanzal. What is Pi?. Pi is the ratio of circumference of a circle to diameter of a circle The symbol for pi. Circumference. diameter. =. Circumference. Diameter. The Value of pi. In all circles, the ratio of circumference to diameter results in the same value:

vaughn
Download Presentation

By Tracy Hanzal

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Pi By Tracy Hanzal

  2. What is Pi? • Pi is the ratio of circumference of a circle to diameter of a circle • The symbol for pi Circumference diameter = Circumference Diameter

  3. The Value of pi • In all circles, the ratio of circumference to diameter results in the same value: • Approximate value: = 3.14159265359……… Pi is an infinite decimal with no pattern in the decimal value. Pi may be used to find the circumference of a circle if the diameter is known or to find the diameter if the circumference is known or also to find the area of a circle. Pi is also used in trigonometry in measuring the radians in a coordinate plane. When approximating the circumference or area of a circle, the value of 3.14 is most commonly used and another value commonly used is the fraction 22/7.

  4. History of Pi • There is evidence that the ancient Egyptians and Babylonians were aware of a common value in circles. • The Egyptians figured a value for pi to be 4 x (8/9)2, which is about 3.16045. This value is not very accurate and difficult to work with. • The Babylonians had an easier number to work with. Records show that their value for pi is 3 1/8, which is 3.125. • Both civilizations approximations of pi are obviously not as accurate as the value we have today, but they knew there was a common ratio and they knew that the value was a little more than three.

  5. Computation of pi from 2000 B.C. More History of Pi

  6. Symbol for pi • Introduced by William Jones in 1706 • The Greek Letter Pi was chosen to represent the value 3.14159….. • The Greek letter, shown at the write is pronounced like our letter “p” which stands for perimeter.

  7. Examples AREA OF CIRCLE = r2 Diameter = 6 cm Find the area of the circle: A = pi x r2 A ≈ 3.14 x (3 cm)2 A ≈ 3.14 x (9 cm2) A ≈ 28.26 cm2

  8. Examples Volume of a Cone: h = 10 cm V ≈ 3.14 x (4 cm)2 x (10 / 3 cm) V ≈ 3.14 x (16 cm2) x (10 / 3 cm) V ≈ 167.467 cm3 r = 4 cm

  9. Works Cited http://www.ualr.edu/~lasmoller/pi.html http://math.forum.org/dr.math/faq/faq.pi.html http://www.cecm.sfu.ca/project/ISC/Pihistory.html http://www.equationsheet.com/eqninfo/Equation-73.html

More Related