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Circular Permutations |
1997-02-05 |
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Ed Varjassy pose la question : I have an understanding of simple problems involving circular permutations but do not understand them when they start to have restrictions. Is there any advice you can give for these more complicated permutations. Penny Nom lui répond. |
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Deriving the Quadratic Formula |
1997-02-04 |
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James pose la question : How do you derive the quadratic formula? I know what it is, but the textbook doesn't say how to derive it. Penny Nom lui répond. |
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Parabolic Mirrors |
1997-01-28 |
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Megan Wennberg pose la question : Consider a ray of light that passes through a chord of a parabola (the chord is above the focus and parallel to the directrix), hits the parabola at a point (x,y) and is reflected through the focus. If d1 is the distance from the chord to the point of incidence (x,y) and d2 is the distance from (x,y) to the focus, can you prove that the sum of the distances d1+d2 is constant, independent of the particular point of incidence. Penny Nom lui répond. |
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A donkey and his carrots |
1997-01-28 |
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Emily Lind pose la question : There is a donkey who carries carrots. A farmer has 3,000 carrots to carry to the market. The market is 1,000 miles away. The donkey can only carry 1,000 carrots at a time and he eats 1 carrot every mile that he walks but this is only when he is carrying carrots. How many carrots can the farmer get to market by having the donkey carrying them? Penny Nom lui répond. |
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Repeating Decimals |
1997-01-24 |
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Grant Reed pose la question : Is there a way to tell that the repeating decimal for 1/17 has no more than 16 repeating digits? Penny Nom lui répond. |
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Foci of an Ellipse |
1997-01-22 |
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David Gilliam pose la question : How do I find the focii of the following equation? 4x^2 + 9y^2 = 36 Harley Weston lui répond. |
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Mathematics of Schedules |
1997-01-16 |
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Byron Krull pose la question : I was asked if there was a mathematical method to work with schedules. The problem is this. There are 24 teams playing weekly on 4 sheets at 3 different times of the day as follows... Denis Hanson lui répond. |
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Three Spheres |
1997-01-14 |
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Alan Schnerch pose la question : Three spheres of diameter 2 are placed on a level surface so that each sphere touches the other two. A fourth sphere, also of diameter 2, is placed on top of the other three so that it touches all of the other spheres. The distance from the level surface to the highest point of the top sphere is . . .. Chris Fisher and Harley Weston lui répond. |
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A triangle problem |
1996-12-19 |
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S. Johnson pose la question : Given that Triangle ABC is a right triangle and Circle O is inscribed in it find the radius of Circle O, totally in terms of a, b, and c. Penny Nom lui répond. |
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A trig problem |
1996-12-13 |
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S. Johnson pose la question : sin t + cos t = 1/5. Find ALL exact values of cot t, given the original equation. Harley Weston lui répond. |
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Roots of a Polynomial |
1996-12-06 |
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Paula Miller pose la question : Why is the solution called a "root"? Why not just the "x-intercepts"? Chris Fisher and Harley Weston lui répond. |
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Sides in a Regular Polygon |
1996-12-06 |
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Rick Moss pose la question : If you are given the measure of each interior angle (162 degrees) of a regular polygon. How many sides does the polygon have? Penny Nom lui répond. |
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A balance problem |
1996-11-18 |
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Jack N. Bussell pose la question : There are 12 coins which look exactly the same, however one of them is heavier or lighter than the rest. Using a pointer balance scale, can you identify the odd coin and whether it is heavy or light in 3 weighings? Harley Weston lui répond. |
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Pentominoes |
1996-11-14 |
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Sam Maraldo pose la question : What is a pentominoe? I need to understand the concept and how/why it is used? Penny Nom lui répond. |
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Trigonometry |
1996-11-12 |
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Evans pose la question : Any idea who came up with some or most of the ideas involved in trigonometry? Chris Fisher lui répond. |
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