Linda Salgado Troup Middle School Mathematicians Are People, Too (Volumes 1 and 2) Reimer & Reimer, Dale Seymour Publications Famous Problems and Their Mathematicians Johnson, Teacher Ideas Press A Peek Into Math of the Past Voolich, Dale Seymour Publications Hands-on Math for Middle Grades Creative Teaching Press Mr. Archimedes’ Bath, Pamela Allen The Librarian Who Measured the Earth, Kathryn Lasky What’s Your Angle, Pythagoras? Julie Ellis The Fly on the Ceiling, Dr. Julie Glass The History of Counting, Denise SchmandtBesserat www.IKeepBookmarks.com account: SalgadoL no password needed List of many websites on mathematicians Rene Descartes France 1596-1650 Co-Founder of Analytic Geometry Combined algebra and geometry creating analytical geometry or coordinate geometry X y z First to use the last letters of the alphabet (x, y, z) for unknown quantities and the first letters of the alphabet (a, b, c) to designate known quantities. Discovered how to calculate the volume of a sphere, and even wanted this diagram on his tombstone. He made so much progress in this area that nothing could be added for 18 centuries. EUREKA (I have found it!) – Bouyancy 2 x Developed Exponential system of writing large numbers Discovered the Law of the Lever This statue in the National Museum in Naples, Italy, was widely claimed to be Archimedes. It is actually a bust of Archidamos III, a third century BC king of Sparta Italian postage stamp honoring Archimedes May 2, 1983 Scott Catalogue Number 1559 Archimedes water screw A 1740 engraving of Archimedes planning the defenses of Syracuse. The Greek writing on his cap is (Archimedes the geometer). A detail of a wall painting in the Stanzino delle Matematiche in the Galleria degli Uffizi in Florence, Italy. Painted by Giulio Parigi (1571-1635) in the years 1599-1600. Archimedes designed many tools for defending Syracuse from invasion. This is a model of how one of Archimedes war gadgets may have worked. Burning Mirror Archimedes used mirrors to reflect and intensify the sun, causing the ships to catch on fire. Wall painting from the Stanzino delle Matematiche in the Galleria degli Uffizi (Florence, Italy). Painted by Giulio Parigi (1571-1635) in the years 15991600. Give me a place to stand and I will move the earth Engraving from Mechanics Magazine London, 1824 The Law of the Lever w1 d1 d2 w2 fulcrum w1 x d1 = w2 x d2 400 pounds ? 5 feet w1 x d1 = w2 x d2 w1 x 5 = 400 x 5 w1 = 400 5 feet 400 pounds ? 8 feet w1 x d1 = w2 x d2 w1 x 8 = 400 x 2 w1 = 100 2 feet Lever Problems • How long would the lever need to be so that you can lift a 20 ton dinosaur? Place the dinosaur 10 feet from the fulcrum and pretend you weigh 100 pounds. • How long would the lever need to be so that you can lift a team of 10 football players (weighing 200 pounds each)? Use the same set-up as above. • How long would the lever need to be so that you can lift a lifetime supply of candy bars? Estimate that you can eat 2 pounds of candy each week for 70 years. Use the same set-up as above. The death of Archimedes depicted on a Roman floor mosaic Benjamin Franklin was a statesman and diplomat for the newly formed United States, as well as a prolific author and inventor. Franklin helped draft, and then signed, the Declaration of Independence in 1776, and he was a delegate to the Constitutional Convention in 1787. As a civic leader, he initiated a number of new programs in Philadelphia, including a fire company, fire insurance, a library, and a university. Ben Franklin discovered electricity, bifocal eye glasses, the odometer and a wood burning stove, among many other things. Ben Franklin sitting on a bench. Artwork on the campus of the University of Pennsylvania. Arrange the numbers 1-9, using each number only once. All rows, columns and diagonals must add to the same number 5 9 1 3 7 4 = 16 = 18 = 11 Arrange the numbers 1-9, using each number only once. All rows, columns and diagonals must add to the same number MEAN = 15 8 2 6 15 Multiply each number by some integer…is it still a magic square? 8 1 6 = 15 3 4 5 9 7 2 = 15 15 15 15 15 = 15 Correct Answer Arrange the numbers 15-23, using each number only once. All rows, columns and diagonals must add to the same number 15 16 17 18 19 20 21 22 23 171 171 ÷ 3 = 57 each row, column, & diagonal Benjamin Franklin’s Numbers 52 14 53 11 55 9 50 16 1. 2. 3. 4. 5. 6. 7. 8. 61 3 60 6 58 8 63 1 4 62 5 59 7 57 2 64 13 51 12 54 10 56 15 49 20 46 21 43 23 41 18 48 29 35 28 38 26 40 31 33 36 30 37 27 39 25 34 32 45 19 44 22 42 24 47 17 Find the sum of any row: Find the sum of any column: Find the sum of the first four numbers of any row: Find the sum of the last four numbers of any row: Find the sum of the first four numbers of any column: Find the sum of the last four numbers of any column: Find the sum of the four corners: Draw a box around a set of 16 numbers the make a 4x4 square. Find the sum of the corners of this square: 9. Draw a box around a set of 36 numbers the make a 6x6 square. Find the sum of the corners of this square: 10. Draw a box around any 4 numbers that make a 2x2 square. Find the sum of the corners. 52 14 53 11 55 9 50 16 61 3 60 6 58 8 63 1 4 62 5 59 7 57 2 64 13 51 12 54 10 56 15 49 20 46 21 43 23 41 18 48 29 35 28 38 26 40 31 33 36 30 37 27 39 25 34 32 45 19 44 22 42 24 47 17 1 + 2 + 3 + … + 98 + 99 + 100 = 5050 Helped his father with payroll accounts at the age of 3 Remembers he could “reckon” before he could talk Know seven languages by the age of 19 Proved construction of a 17 sided polygon with only a compass and straight edge, thought impossible for 2000 years. Gauss wanted a heptadecagon placed on his gravestone, but the carver refused, saying it would look like a circle. The heptadecagon is used as the shape of the pedestal with a statue honoring Gauss in his home town of Braunschweig. Gauss on the 10 Mark note F F D D D D C C C C C C B B B B A A His motto was "pauca sed matura" (few but ripe). His diary that covered 20 years of work only contained 19 pages. Gauss was a perfectionist. After his death it was discovered that many discoveries credited to others had first been worked on by Gauss years earlier. Much of his work was never published because he felt it wasn’t finished yet. Eureka (num) = + + 1 3 Eureka (num) = 6 + 10 + 15 This entry from Gauss’ diary meant that every number could be written as a sum of three or fewer triangular numbers. Triangular Numbers: 1, 3, 6, 10, 15, 21, 28… Number = Sum of 3 or fewer 1 2 3 4 5 6 7 8 9 10 11 12 6+1 6+1+1 6+3 Number = Sum of 3 or fewer 37 21 + 15 + 1 Pythagoras is often considered the first true mathematician. The Pythagorians believed “All is Number,” meaning that everything in the universe depended on numbers. They were also the first to teach that the Earth is a Sphere revolving around the sun. Many of Pythagoras’ beliefs reflect those of the Egyptians. The Egyptian priests were very secretive. The refusal to eat beans or wear animal skins and striving for purity were also characteristics of the Egyptians. a2+b2=c2 The sum of the angles of a triangle is equal to two right angles or 180 degrees Venus as an evening star was the same planet as Venus as a morning star. The five regular solids The abstract quantity of numbers. There is a big step from 2 ships + 2 ships = 4 ships, to the abstract result 2 +2=4 Regular Solids • Tetrahedron • Cube • Octahedron • Dodecahedron • Icosahedron Regular Solids • Measure the nets of the regular solids and find the surface area One of the Pythagorian’s most important discoveries was that the diagonal of the square is longer than its sides. This showed that irrational numbers existed (decimal numbers that never end). c a b a<c b<c Joseph-Louis Legrange France 1736-1813 Started studying mathematics seriously at age 15; appointed a professor of mathematics at age 17 Helped design the metric system, base 10 instead of base 12 Answered a 50-year old question concerning constant perimeter with largest possible area Given a constant perimeter, which shape will have the greatest area? Each student (or group) needs • Several sheets of centimeter grid paper • Several pieces of yarn cut to the same length (constant perimeter ≈ 30 cm) • Tape Students will tape the string to the grid paper to make a polygon, then estimate the area of the polygon. One of Legrange’s most significant discoveries in the area of Number Theory: Every positive integer can be expressed as a sum of four or fewer square numbers. 1x1=1 2x2=4 3x3=9 Square Numbers: 1, 4, 9, 16, 25, 36… Number = Sum of 4 or less squares ■ 1 2 3 ■ 4 4+1 5 4+1+1 6 7 4+1+1+1 4+4 8 ■ 9 10 Number = Sum of 4 or less squares 47 36 + 9 + 1 + 1 Mary Everest Boole England 1832-1916 1 2 3 4 5 6 7 1 2 3 4 5 6 7 Line Designs Or String Art www.Mathcats.com/crafts/stringart.html