







Archimedes Burning Mirror 
20120717 

From Frakeetta: Archimedes Burning Mirror
There is a story about Archimedes that he used a “burning mirror” in the shape of a paraboloid of revolution to set fire to enemy ships in the harbor. What would be the equation of the parabola that one would rotate to form the appropriate paraboloid if it were to be designed to set fire to a ship 100m from the mirror? How large would the burning mirror need to be? What is the likelihood that this story is true? Answered by Robert Dawson. 





Why is the letter Z used for the integers? 
20120611 

From ROSE: WHY is that the acronym of integers is represented by letter Z or J? Answered by Chris Fisher. 





The difference in latitudes of two cities 
20120118 

From Renee: Assuming that the earth is a sphere of radius 6378 kilometers, what is the difference in latitudes of two cities, one of which is 600 kilometers due north of the other? Answered by Robert Dawson. 





The development of the Pythagorean theorem 
20110408 

From Ataa: I am doing a assignment on Pythagorean Theorem and i am stuck on the subquestion
development of the Pythagorean theorem and i really need help can u give me accurate info
for this because i am not finding anything!!!thanks in advance.
Yours truly
AUMAKHAN Answered by Chris Fisher. 





More on millions and billions 
20100311 

From julio: shouldn't the thousands of millions, tens of thousands of millions, and hundreds of thousands of millions be called what they are? technically they are not billions because billions come after 999,999,999,999 . It would sound better to call the numbers by their real name when economists talk about the national deficit besides mathematics is a very precise science that doesn't admit mistakes. Or am I wrong? I know that in other countries is expressed different than here. I have this question to different people and nobody has a "logical" explanation to it. " that's the way is here in the US" does not explain any thing Answered by Penny Nom. 





What is the exact value of pi? 
20080927 

From mahesh: what is the exact value of pi.
22/7 is accurate value of pi, if not then how can i find out the exact pi value. Answered by Harley Weston. 





JeanCharles de Borda 
20080829 

From Joanne: I am researching JeanCharles de Borda as a mathmatician. What was his work focused on and where can I find more information? Answered by Penny Nom. 





The perimeter of a regular polygon 
20070918 

From Ashwynn: why does the area of regular polygons with a perimeter of 1000m increase as the number of sides increase? Answered by Stephen La Rocque. 





Does every number have a square root? 
20070910 

From Cheryl: Does every number have a square root? Answered by Harley Weston. 





What is the origin of pi? 
20070430 

From Aastha: from where has been tha value of "pi" derived? or what is the origin of "pi" Answered by Penny Nom. 





What is pi? 
20070309 

From Billy: What is pi? Answered by Jaymi Peterson and Sara Ulmer. 





What value of pi did the Indians use? 
20070306 

From gigi: What value of pi did the indians use? Answered by Penny Nom and Sara Ulmer. 





The writing of numerals 
20070223 

From Abbas: What is the reason to write the integral such that one as 1 two as 2 similarly three as 3 and vice versa Answered by Penny Nom. 





Who invented the division symbol? 
20061229 

From Alex: Who invented the division symbol? Answered by Penny Nom. 





The history of the meter 
20061023 

From Caitlyn: i'm an 8th grade student and i have a lab report due and i really need to find out more about the history of the meter. Answered by Stephen La Rocque. 





History of mathematics 
20060906 

From Sharon: i am looking for the history of math could you help Answered by Stephen La Rocque. 





The development of trigonometry 
20060815 

From Eugene: Can you please give the exact time line of trigonometry. Answered by Penny Nom. 





How old is y = mx + b? 
20060705 

From Beckie: I am taking intermediate algebra this summer (Math 95), and have a question for you. My instructor will award extra credit points to any of us who find out how old the formula
y = mx+b is. Would you happen to know the answer? Answered by Penny Nom. 





Mayan multiplication 
20060416 

From Marca: I'm researching the Mayans, and my advisor, Dr. McDonald, stated that you may know whether the Mayans knew how to multiply. I'm finding conflicting information on the internet, and anything you could provide would be greatly appreciated. Answered by Chris Fisher. 





Right angles 
20060125 

From AshLee: I was recently given a challenge in my Algebra class. My teacher wanted to know about a right angle. He said he would give five bonus points to the person that could bring in information. (I know five bonus points may not seem like a lot but in this class, they are.) I looked on this site and I found out why it was called a right triangle, but my teacher want to know where did that theory come from. I was wondering too... not just because of the bonus points. Answered by Penny Nom. 





BEDMAS 
20051124 

From Judy: My name is Judy and I am a grade 6 teacher.
We have just started our lessons on the order of operations and my students have asked me why we have BEDMAS and what is the logic to it.
Is there a reason that that we do math in this particular order?
Who invented this rule or how was it decided on and when? Answered by Walter Whiteley. 





The horizontal fraction bar 
20040527 

From Kashia: What is the name of the bar that separates a numerator and that denominator? Answered by Penny Nom. 





Ratio and proportion 
20040402 

From Kenneth: The terms of a ratio in a proportion are often expressed as a is to b as c is to d.
Example: 2/4 = 6/12 this proportion represents that 2 is to 4 as 6 is to 12.
What does the "a is to b as c is to d" really represent or indicate in ratios? Answered by Claude Tardif. 





Johann Muller 
20040314 

From A student: What major contributions to spherical trigonometry did Johann Muller make? Answered by Penny Nom. 





Zero 
20040212 

From Syazwan: can you tell me who and when the number zero was
discoveredd Answered by Penny Nom. 





Order of operations 
20040128 

From John:
I am trying to find out any information concerning the development of the order of operations. for example, when (why/how) did it become the case that 2 + 3 x 5 =17, rather than 25.
any insight is appreciated. Thank you.
Answered by Penny Nom. 





Polynomials 
20040125 

From Bruce:
A polynomial is defined as
Polynomial functions are functions that have this form:
f(x) = a_{n}x^{n} + a_{n1}x^{n1} + ... + a_{1}x + a_{0}
The value of n must be an nonnegative integer. That is, it must be
whole number; it is equal to zero or a positive integer.
The coefficients, as they are called, are a_{n}, a_{n1},
..., a_{1}, a_{0}. These
are real numbers.
Questions:
 why must n be positive?
 what are some historical facts
about the evolution of the definition?
Answered by Harley Weston. 





Aristotle 
20031121 

From John:
I would like to know how aristotle was related to math.
In all my searches I have found only philosophy etc.
But not any math.
Answered by Penny Nom. 





An inch and a millimeter 
20030621 

From Greg: The conversion factor for inches to millimeters 25.4 It strikes me as very odd that it's not some infinite decimal. I could understand this if one system was derived from the other but as I understand it they were derived independently. Is the conversion 25.4 or 25.4000XXXXXXX? If it's just 25.4 then how did that happen? Answered by Harley Weston. 





The metric and Imperial systems 
20030608 

From Ashlee: i am a year 8 student, and i am doing my Maths talent quest on the Metric and Imperial number system.
i was wondering, where did the 2 systems orginate and if possible, a little bit or information.
I also need to know the conversions of ounce, foot, mile..etc..from imperial to metric. Answered by Penny Nom. 





Why quadratic? 
20030121 

From Dan: Why are equations of the form aX^{2} + bX + c =0 call quadratic? The quad indicates 4 but the power is 2. Answered by Penny Nom. 





Radians 
20030116 

From Erikson: I am a student in the 10th grade and attending advanced math at my high school. I was assign to do a report about the unit circle and the radian. But there seems to be no information available about the history of the radian; who first found out about them, which civilizations used it if any. Well, hopefully you'll assist me in this troubling question. Thank you for your kind consideration. Answered by Penny Nom. 





What is larger than infinity? 
20030112 

From Dana: What is larger than infinity? Answered by Claude Tardif and Harley Weston. 





Why do integers have the symbol of Z? 
20020111 

From Stephanie: Why do integers have the symbol of Z? Natural numbers have the symbol of N, whole numbers have the symbol of W. Our professor has asked us to find out why the letter Z is represented for integers. Answered by Penny Nom. 





60 seconds in a minute 
20011011 

From Andy: I am a fourth grade teacher. Yesterday my students asked "Why are there 60 seconds in a minute?" Which also led to 60 minutes in an hour? I have had trouble determining why the number 60? Any help would be appreciated. Answered by Penny Nom. 





Mystery mathematician 
20011008 

From A student: Theres a mathematician that was born on October 16 1879 in England and died on October 1 1921 in England. Suffered from severe disabilities. Did poorly in his degree and settled for a pass degree. Was awarded the Allen scholarship for research in 1904. He also applied logic to Physics in papers such as On Some Points in the Foundation of Mathematical Physics (1908). Who is it? Answered by Claude Tardif. 





Standard deviation 
20010922 

From Doug: I was wondering if anybody knows who the founder of standard deviation was? Answered by Penny Nom. 





Euclid and Pythagoras 
20010614 

From Scott: Question 1. In about 300 BC Euclid recorded a proof of Pythagoras rule. Disscuss Euclid's contribution to developing the theroem. Question 2. Why was it named after Pyhagoras if he did not orginally discover it? Answered by Chris Fisher. 





Pi 
20010524 

From Mary: Where does the term pi come from and how many digits are actually in pi? Answered by Penny Nom. 





Camille Jordan 
20010322 

From Missy: PLEASE SEND ME INFORMATION ON CAMILLE JORDAN AND HIS WORK IN ABSTRACT ALGEBRA Answered by Rick Seaman. 





The "goesinta" box 
20010207 

From Bridget: We are looking for the "proper" name of the "box" that is drawn around the dividend on a division problem: ___ 3)12 It has always been a family joke to call it the "goesinta" box, but a search of several reference sources hasn't yielded an answer  This is a question of curiosity rather than a question for homework. Answered by Claude Tardif. 





The Pythagorean Theorem 
20010108 

From Megan: Why the Pythagorean Theorem so important in our lives and what is it's history? Answered by Penny Nom. 





Women mathematicians 
20010107 

From Kisha: Can you please tell me names of at least five female math teachers who changed history back then? Answered by Penny Nom. 





Fibonacci 
20001207 

From A student: Can you give me any info about Fibonacci?? Answered by Penny Nom. 





Henri Leon Lebesgue 
20001114 

From Mandy: I have a report that I have to do on Henri Leon Lebesgue for my Foundations of College Math class. I have searched for him on erols, google, yahoo and a few other search sites and I have only come up with one page that offered some information. I was wondering if anyone knew anything about him, or a web page that I could get some info. Answered by Harley Weston. 





Numerator and denominator 
20000618 

From Maureen Beard: What is the origin of the terms numerator and denominater? Answered by Penny Nom. 





Volume of a sphere 
20000521 

From Kevin Partridge: Does anyone have a way to physically demonstrate how to explain the volume formula for a sphere? Or perhaps how to derive the formula without calculus? Answered by Harley Weston. 





Mary Fairfax Greig Somerville 
20000503 

From Joshua Garrett: I'm giving a report in class on her life. Could i recieve some sort of information about her. thank you Answered by Claude Tardif. 





2^32 + 1 
20000408 

From Un Etudiant: 2^{32} +1 can be divided by 641 , why? Answered by Claude Tradif. 





History of a meter 
20000407 

From Jarod Fischer: The length of a meter has been determined in three different ways. The first and original way was determined in 1798. The second way was determined in 1960. The third and current way was determined in 1983. What were the three ways and why were the first two abandoned? Answered by Harley Weston. 





The side length ratios of some triangles 
20000404 

From Alexis Lockwood: I am doing a project for my Math 30B class regarding the side length ratios of 454590 degree and 306090 degree triangles. I would really appreciate any assistance in answering the following questions, or even direction to an appropriate web site or resource on the matter. Answered by Harley Weston. 





Pi 
20000222 

From Shelley Collier: Numbers that can be written in the form p/q where p and q are integers, (q not 0), are known as rational numbers. What you are missing is that p and q must be integers. The fact that Pi is irrational means that you can't have a circle with both the circumference and diameter being integers. In fact you can't even have the circumference and diameter both rational since the quotient of two rationals is again a rational. Answered by Claude Tardif and Penny Nom. 





Why counterclockwise? 
20000221 

From Drew: Why do the numbers of quadrants in a graph increase in a counter clockwise pattern? Why aren't they numbered increasingly in a clockwise pattern? Answered by Chris Fisher. 





A 16th century mathematician 
20000204 

From Danielle Dombrowski: My name is Danielle Dombrowski, I am in the 7th grade and my teacher gave us a riddle to figure out which mathemtician we would have to do a report on. The only problem is that I don't know what the answer is. Can you help? The riddle is "This 16th century mathematician, having predicted the day of his death, took poison to make sure it came true. Who is it?" Answered by Penny Nom. 





zero 
20000101 

From Jason: What civilization first used zero? Answered by Penny Nom. 





Comma as decimal separator 
19991218 

From Franck Menuge: Could somebody tell me the origin of the use of a 'comma' as a decimal separator and of a 'dot' for thousands in the French numeric system, ex.1.234,56 Is it only used in France or in other european coutries? Why is it different in the UK? Answered by Patrick Maidorn and Penny Nom. 





Ben's observation 
19991028 

From Emily Nghiem and Ben Rose: As a teacher at a school called Educere in Houston, I have a ninthgrade student who discovered the following shortcut last year as an eightgrader. What he noticed is that given any two consecutive integers (or n and n+1 for any rational number greater than or equal to 2), the difference between their squares was equal to the sum of the two numbers. . .
Answered by Chris Fisher and Penny Nom. 





Women in Trig 
19991011 

From Sandra Mills: I am looking for some information about women who have contributed to the discipline of trigonometry. In addition to this I have been asked to choose a subject pertaining to Roman times for my Roman and American Lit class. I wanted to do a project and presentation related to mathematics, but could use some suggestions maybe how mathematics were applied as in engineering and the structure of the Roman buildings. Could you please provide some information about the history of mathematics and it's applications in Roman times. I am also open to any other suggestions for topics. Answered by Chris Fisher. 





Trigonometry history 
19990925 

From Nikki: What is trigonmetry ? Who invented it ? What is it's purpose ? And anything else that you can tell me that is related to Trigometry. Answered by Chris Fisher. 





Help with three mathematicans! 
19990914 

From Ashley Tacheira: I am a sophomore in high school and have been assigned a research paper on over thirty mathematicians. I was able to find information on all but three. I need to know the birth and death dates and major contributions of these three mathematicians. Any suggestions on where to look would be appreciated. George Stigler, T.C. Koopmans and Thomas Guthrie are the three that I cannot seem to find. Answered by Chris Fisher. 





Degrees and triangles 
19990909 

From Sandra Mills: Are there any triangles which are not 180 degrees? I am also in need of information on the history of degree measure for an angle. Answered by Walter Whiteley. 





Infinity Symbol 
19990713 

From Mark E. Kelly: There is a symbol that looks like a sideways 8 that is used to represent infinity. Does it have a name? Answered by Doug Farenick and Penny Nom. 





y=mx+b 
19990415 

From Selena Royle: When solving a problem on slopes,and in the formula y=mx+b what do the M and B stand for? Why M and B? Answered by Penny Nom. 





Trigonometry history 
19980526 

From Joeseph Huckler: Can you please tell me some history of the trigonometric ratio Tangent? who discovered it? when was it discovered and some other useful info... Answered by Penny Nom. 





The origin of angles 
19980224 

From Marc Poulin: I'm currently teaching angles to students in grade 10 and I've been asked what's the origin of the terms degrees, radians and gradians. I know that the radians come from the sexagesimal numerical system of the Babylonians but my kids wanted to know dates and persons who would have brought these terms first. Answered by Harley Weston. 





Tangrams 
19980224 

From Allison: Do you know the story behind the tangram? I know that it is a Chinese puzzle about 200 years old. If there is a story about its creation, I would love to share it with my 7th graders. Thanks. Answered by Diane Hanson and Penny Nom. 





Square Root History 
19970829 

From Carlos Montecel S.: I need find information over the "Square Root History", Could you help me? Answered by Harley Weston. 





The Division Bracket. 
19970409 

From Judy Riley: A fellow teacher recently asked if I remembered the exact word for a division bracket (not the symbol with dots, the horizontal line in a fraction, or a solidus). I couldn't. Can you help? Answered by Walter Whiteley and Harley Weston. 





Why QUADratic? 
19970319 

From Paula Miller: A student today asked me why a quadratic, with highest power of degree 2, was called a QUADratic. We're awaiting the answer with baited breath! :) Answered by Chris Fisher and Walter Whiteley. 





A Presidential Proof 
19970318 

From Greg Smith: Which US president developed a proof for the Pythagorean Theorem? Where can a copy of the proof be located? Answered by Chris Fisher and Harley Weston. 





The Real Pythagoras 
19970316 

From Michael Gaskin: I am wondering if you have any information about Pythagoras and his accounts in math. Answered by Chris Fisher. 





Roots of a Polynomial 
19961206 

From Paula Miller: Why is the solution called a "root"? Why not just the "xintercepts"? Answered by Chris Fisher and Harley Weston. 





Trigonometry 
19961112 

From Evans: Any idea who came up with some or most of the ideas involved in trigonometry? Answered by Chris Fisher. 





Could you tell me the name for the bar in a division problem? 
19961021 

From Linda: Could you tell me the name for the bar in a division problem. Not the line with dots on either side but the line that divides the two numbers? My name is Linda. I am asking for my niece who is in 8th grade. Answered by Chris Fisher. 





Why is a circle divided into 360 degrees? 
19960930 

From Kurtis Kredo: I was recently wondering why a circle has been divided in to 360 degrees. When I asked my physics teacher he could not think of an answer. His guess is that it probably has to do with people long ago using the base 6 number system. I have a small inkling that it has to do with easy conversion or usage with radians or grads. Answered by Chris Fisher. 





isomorphisme 
20000810 

From Romain Kroes: Pour les beoins d'un ouvrage d'économie que je suis en train de terminer, pouvezvous me dire qui est (sont) l'inventeur de l' "isomorphisme" en mathématiques (calcul tensoriel)? Answered by Claude Tardif. 

