### Volume 4, Number 6

 ``` 8 February 1999 Vol. 4, No. 6 THE MATH FORUM INTERNET NEWS Sketchpad for Little Ones | FAQs: Proofs, Formulas |Triumph of the Nerds SKETCHPAD FOR LITTLE ONES - Geri Anderson-Nielsen http://mathforum.org/sketchpad/littleones/ The Geometer's Sketchpad (GSP) is a powerful tool for discovering geometric properties. The program contains a ruler, a protractor, a calculator, and a simple word processor, in addition to graphing possibilities for the Cartesian plane. The activities illustrated are samples of those used in the Lower and Middle School mathematics classes at Georgetown Day School, and were first assembled for a handout for presentations made at the 1998 NCSM/NCTM Annual Meetings. Activity Grades Exploration all Lines, Rays, and Segments 3-5 Acute, Obtuse, and Straight Angles 2- Guess the Angle 2- Area and Perimeter 3- How Many Degrees in a Triangle? 4- Circles 4- How Many Degrees in a Quadrilateral? 4- Sum of the Interior Angles of a Polygon 4- Student-Made Quiz 7 Similar Triangles 7 Transformations 7 -|-\-/-|-\-/-|-\-/-|-\-/-|-\-/-|-\-/-|-\-/-|-\-/-|-\-/-|-\-/-|- New from the Dr. Math FAQ: Proofs, Formulas PROOFS http://mathforum.org/dr.math/faq/faq.proof.html What is a proof? How do you write a two-column proof? This new FAQ from the Math Forum's project Ask Dr. Math provides excerpts from and links to answers from the Dr. Math archives. For more discussions pro and con about two-column proofs, search the archives of the newsgroup geometry-pre-college for the words two column proof and browse the threads returned: http://mathforum.org/discussions/epi-search/geom.pre-college.html See also these three articles from Alexander Bogomolny's interactive monthly column for MAA Online, "Cut the Knot" (you will need a Java-enabled browser): - Proofs Without Words http://www.cut-the-knot.com/ctk/pww.html - Pythagorean Theorem - includes over 20 proofs http://www.cut-the-knot.com/pythagoras/ - Proofs in Mathematics - a discussion of the value of proofs in the classroom, followed by a collection of proofs classified as "simple" or "charming" http://www.cut-the-knot.com/proofs/ \|/ ANALYTIC GEOMETRY, TRIGONOMETRY FORMULAS http://mathforum.org/dr.math/faq/faq.formulas.html Robert L. "Dr. Rob" Ward has added two new units to the FAQ area on formulas: - Analytic Geometry Formulas cover one, two, and three dimensions: points, directions, lines, triangles, polygons, conic sections, general quadratic equations, spheres, etc. - Trigonometry Formulas provide definitions of trigonometric functions and formulas for bounds, identities, relations in right and oblique triangles, and inverse trigonometric functions. -|-\-/-|-\-/-|-\-/-|-\-/-|-\-/-|-\-/-|-\-/-|-\-/-|-\-/-|-\-/-|- TRIUMPH OF THE NERDS: A HISTORY OF THE COMPUTER Robert X. Cringely, PBS Online http://www.pbs.org/nerds/ Learn how youthful amateurs, hippies, and self-proclaimed "nerds" accidentally changed the world. This companion site for the Public Broadcasting System television special hosted by Robert Cringely, "Triumph of the Nerds: The Rise of Accidental Empires," presents a tour of the history of the computer from the abacus to the World Wide Web. Highlights include: - Transistors (1947) - Doug Engelbart and the minicomputer (1968) - Apple II (1977) - The IBM PC (1981) - TV program transcripts http://www.pbs.org/nerds/timeline/ -|-\-/-|-\-/-|-\-/-|-\-/-|-\-/-|-\-/-|-\-/-|-\-/-|-\-/-|-\-/-|- CHECK OUT OUR WEB SITE: The Math Forum http://mathforum.org/ Ask Dr. Math http://mathforum.org/dr.math/ Problems of the Week http://mathforum.org/pow/ Internet Resources http://mathforum.org/~steve/ Teacher2Teacher http://mathforum.org/t2t/ Discussion Groups http://mathforum.org/discussions/ Join the Math Forum http://mathforum.org/join.forum.html Send comments to the Math Forum Internet Newsletter editors _o \o_ __| \ / |__ o _ o/ \o/ __|- __/ \__/o \o | o/ o/__/ /\ /| | \ \ / \ / \ /o\ / \ / \ / | / \ / \ ```