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- What Does "Stellated" Mean? [03/31/1998]
Stellating polyhedra, including solids that are already stellated.
- What is a continued fraction? [03/06/1998]
What is a continued fraction and what makes it different from the types
of fractions or ratios I'm used to?
- What is a Cuboctahedron? [01/02/2001]
What is a cuboctahedron?
- What is a Functional Transformation? [08/11/2002]
I would like a brief definition of a functional transformation and
what an application is in early Calculus.
- What is a Median? [03/03/1998]
A definition of median, and four examples of calculating medians.
- What is an N-gon? [06/01/1998]
Can you explain the statement: "In an N-gon, n-3 diagonals can be drawn
from one vertex"?
- What is a point? [8/26/1996]
Define a point, please.
- What is a Property? [11/29/2001]
I understand Undefined and Defined terms and Axioms and Theorems, but
what exactly is a Property? Is it the same thing as a Theorem? Also what
is a Law?
- What is a Set? [04/04/1997]
What is the correct term to refer to groups of objects like 3 cars, 7
pencils, or 5 apples?
- What is a Sign? [04/21/2003]
Can you do anything in math without signs?
- What is a slide rule? [07/27/1997]
What does a slide rule do and how does it work?
- What Is a Theorem and Why Are They Important? [08/15/1997]
I don't understand how theorems help us learn.
- What is Dimensional Analysis? [11/26/2001]
What is dimensional analysis and how does it work?
- What is Length in a Rectangle? [05/31/1999]
Is the length of a rectangle the longest side, whether vertical or
- What is Math? [10/04/1997]
Is math a science, an art, or some other anomaly?
- What is Meant by "the Sum of a Series"? [10/21/2003]
A series is the sum of consecutive terms. So why do many authors
speak about "the sum of a series" if the name "series" already means
"sum of consecutive terms"?
- What is the Definition of 'Number'? [01/26/2006]
I think of a number as a symbol for a measure of magnitude, like how
many of something there are. You can't have 2 + i things, so how can
that be a complex 'number'? How do you define what a number really is?
- What Motivates New Definitions? [02/06/2000]
Why do so many mathematical objects -- groups, fields, rings, vector
spaces -- have nearly identical definitions and properties? Does every
new object have to undergo some rigorous proof of its existence?
- What Skew Lines Are and Aren't [01/14/2004]
A description of skew lines including diagrams and definitions.
- When is the expression Q.E.D. used? [02/15/1999]
More on Q.E.D.
- Why Cubed? [11/27/2001]
Why do we use "cubed" for the volume of a figure?
- Why Does 0^0 = 1 and Not Undefined? [11/30/2007]
Your proof for why x^0 = 1 uses a law which breaks down at x = 0. Then
in your definition for 0^0 you side significantly in favor of 0^0 = 1
based on your rule for x^0 = 1 (which was based on a law that breaks
down at 0). Based on what I've read I would side in favor of
undefined. Are there any more conclusive reasons for siding with 0^0 = 1?
- Why Do We Have Leap Year ? [02/25/1998]
Why do we need to have one extra day each 4 years?
- Why Is a Circle 360 Degrees? [07/01/1998]
Why is a circle defined as 360 degrees?
- Why is a Telescoping Series Called Telescoping? [03/29/2008]
I understand what a telescoping series is, but I'm curious why it is
referred to as 'telescoping'. What's the reason for that name?
- Why is K Used as an Abbreviation for Area? [11/29/2004]
Many textbooks use the letter K to represent area in formulas, instead
of A. Do you know why that is?
- Why Isn't a Kilobyte 1,000 Bytes? [03/29/2001]
If the prefix kilo- means 1000, why is a kilobyte 1024 bytes instead of
- Why Is Slope Rise Over Run and Not Run Over Rise? [03/05/2005]
We were wondering today in math class why slope is defined as rise
over run and why it couldn't be run over rise?
- Why They're Called Direction Cosines [09/11/2003]
I would like to know how to find the angles between a 3D vector and the
3 coordinate axes, given the components of the vector.
- Why Use Q and Z? [09/12/2001]
Why is the letter Q used for rational numbers and Z for integers?
- Writing Sigma Notation [02/03/1999]
What does the equation that goes under the Sigma notation imply?