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	The General Equation of a Parabola		1997-05-28
		From Michelle: My name is Michelle and I am a 10th grade student in algebra 2 w/ analysis. I am doing a report on parabolas and I need to know what the general equation is. I've looked in books and keep finding different ones! I also need to know how they can be used in nature. Thank you so much for your time. I really appreciate it! - Michelle Answered by Harley Weston.
	The Area of a Trapezoid.		1997-05-07
		From Mary George: I am doing the area of trapezoids and mixed polygons and I was wondering if you can help me figure out this problem. A line segment drawn parallel to a leg of a right triangle divides the other leg into segments of 3cm and 6 cm and the hypotenuse into segments of 5cm and 10 cm. The two figures formed are a triangle and a trapezoid. Find the area of each. I would appreciate if you would email me back the solution. Answered by Harley Weston.
	Surface Area		1997-04-30
		From Amber Nobile: The height of a cylinder is twice the diameter. Express the total surface area as a function of the height h. Answered by Harley Weston.
	A proof that e is Irrational.		1997-04-30
		From Peter Hall and Jenny: We have a little mathematical problem... we need some help proving e is an irrational number! We don't feel very confident in our formulas, so if You have the time to give us a little explanation we would be very grateful!!! Answered by Doug Farenick and Penny Nom.
	Solving a Trig Equation.		1997-04-28
		From Susan Harvey: Hi I am a teacher and have a calculus problem that I have a solution to but it seems so involved that I would be interested to see if their were other solutions. Solve for x, if x is from -90 to 90 degrees tan2x = 8cos{squared}x - cotx Answered by Chris Fisher Denis Hanson and Harley Weston.
	Formulae for Surface Area.		1997-04-28
		From Gary Millward: I'm trying to help my son with his Math homework (Grade 10) and he has to find the surface area of a cone and rectangluar pyramid. We have the formulas for the volume of these solids, but can't seem to locate the formulas for surface area. Answered by Walter Whiteley.
	A Monte Carlo Procedure		1997-04-23
		From Donna Hall: A irregularly shaped object of unknown area A is located in the unit square 0<=x<=1. Consider a random point uniformly distributed over the square. Let X = 1 if the point lies inside the object and X = 0 otherwise. Show that E(X) = A. How could A be estimated from a sequence of n independent points uniformly distributed over the square? How would you use the central limit theorem to gauge the probable size of the error of the estimate. Answered by Harley Weston.
	Natural Logarithm Functions		1997-04-23
		From Rickson: The following two questions are some of my son's homework that he is having trouble with......any advice or assistance would be appreciated. (eX)5=1000.............the X and 5 are exponents lnx + ln(x+3) = ln10 In each question the problem is to find x. Answered by Harley Weston.
	Square Roots and Functions.		1997-04-23
		From Ed: 1. In most texts the solution to a question such as square root x = -6 is x is undefined. Yet when teaching to solve xsquared = 36 x = +6 or -6 There appears to be a contradiction here. My question is when, where and why do we use the principle square root, not both + and -? This often occurs as the extraneous root in the solution of radical equations and in stating the domain and range of functions involving square roots. 2. Are there any simple rules for determining whether equations are functions without graphing them and doing a vertical line test? Answered by Harley Weston.
	The Central Limit Theorem		1997-04-21
		From Donna Hall: A skeptic gives the following argument to show that there must be a flaw in the central limit theorem: We know that the sum of independent Poisson random variables follows a Poisson distribution with aparameter that is the sum of the parameters of the summands. In particular, if n independentPoisson random variables, each with parameter 1/n, are summed, the sum has a Poisson distributionwith parameter 1. The central limit theoren says the sum tends to a normal distribution, butPoisson distribution with parameter 1 is not normal. What do you think of this argument? Answered by Neal Madras.
	Proofs		1997-04-13
		From Daniel: I'm having trouble understanding proofs. I don't know how to come up the answers on my own. I search through the book looking for the answer. I understand what they are doing, but I don't know how to do it. Answered by Walter Whiteley.
	The Division Bracket.		1997-04-09
		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.
	A Geometry Problem		1997-04-09
		From Gina M. Pisco and Rebecca Henry: Three segments of 3, 4, and 5 inches long, one from each vertex of an equilateral triangle, meet at an interior point P. How long is the side of the triangle? Answered by Richard McIntosh.
	Equation of a line		1997-04-08
		From Susan Gregson: I am a secondary school teacher. My students and I would like to know why the letters m and b are traditionally used to stand for slope and Y-intercept in the standard form of an equation. Was this an arbitrary choice? Who made it? Are the letters from Greek ot Latin words? Answered by Harley Weston.
	Graphing Inequalities of Conic Sections		1997-03-24
		From James Sheldon: I'm trying to graph Systems of Conic Sections with inequalities, but I'm running into problems on which area to shade: x^2+y^2 is greater than or equal to 16 xy > 4 So I graph these two equations, and then my teacher said to substitute a point into it but I'm still not sure how to do it... Answered by Penny Nom.

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