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The quadratic formula |
2003-08-31 |
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From Alex: I am using Houghton Mifflin's Precalculus with Limits book, 2nd edition. However, the first chapter encompasses Algebra review, and I am stuck on a problem. All that's required is to solve the following and verify using a calculator: 3y2+6y+2=0 I have solved the problem using the quadratic formula, but from what I remember, the quadratic formula is used in the case of equations following the AX2+BX+C=0 pattern. As the problem I am attempting uses a y-variable, can I still use the quadratic formula? Since I am not sure what route to take in solving this problem, I am hoping you can assist me. Answered by Harley Weston. |
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Newton's binomial theorem |
2003-08-30 |
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From William: According to page 126 of Murtha & Willard's "Statistics and Calculus" (Prentice-Hall, 1973), Newton's binomial theorem can proved inductively. I suppose that was his method, which I would like to see. Answered by Penny Nom. |
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I can Guess your birthday |
2003-08-29 |
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From Michelle: Hi I am trying to explain to my children how this problem works. It was sent to me on the internet and I can not figure it out. They keep asking me how it works and I can not tell them. The problem is: "I can Guess your birthday:: Answered by Penny Nom. |
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Hauteur d'un tétraèdre irrégulier |
2003-08-29 |
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From Thibault: Je cherche à connaître comment calculer la hauteur d'un tétraèdre irrégulier (aucune arêtes égales) en ne connaissant que la longueur des arêtes. Answered by Claude Tardif. |
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How many cubic yards must I purchase? |
2003-08-29 |
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From Walt:
I am trying to determine how much top soil I must purchase (by the yard). The area is 80' x 15' and I want it 3" thick. How many cubic yards must I purchase? Answered by Penny Nom. |
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Converting to base 10 |
2003-08-28 |
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From Karen: My son is in 5th grade.Ý He is learning how to convert numbers from base 2 to base 10, and base 5 to base 10.Ý Can you explain it to me in the simplest terms? Answered by Penny Nom. |
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Graphing a piecewise function |
2003-08-24 |
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From Amber: How do i begin to graph a piecewise function, absolute function or step function? Answered by Penny Nom. |
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Simplify |
2003-08-24 |
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From Jessica: I have been asked to simplify the expression (5a2)(-2b2)(3b)+(7a2)(2b2)+(-3a)(-5a)(4b) and the answer is apparently 44(a2)(b2). For the life of me I can't figure out how they derive this. Answered by Penny Nom. |
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Why is 5 to the 0 power always 1? |
2003-08-24 |
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From Crystal: Why is 5 to the 0 power always 1? Answered by Penny Nom. |
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A rule with a variable |
2003-08-24 |
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From Crystal: what is a rule with a variable Answered by Penny Nom. |
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X.9999... and X+1 |
2003-08-23 |
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From David: I have read your answers to the questions on rational numbers, esp. 6.9999... = ? and still have a question: The simple algebraic stunt of converting repeating decimals to rational numbers seems to work for all numbers except X.999999.... where X is any integer. The fact that the method yields the integer X+1 in each case seems to violate the completeness axiom of the real numbers, namely that there is no space on the number line which does not have an number and conversely that every geometric point on the number line is associated with a unique real number. In the case of 3.999... for example, it seems that both the number 4 and the number 3.9999.... occupy the same point on the number line. How is this possible??? Answered by Penny Nom. |
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A golf tournament |
2003-08-23 |
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From Dale: I am running a golf tournament with twelve golfers. We will be playing four rounds of golf. I don't want to schedule the same two players together more than twice (if possible). How would I make a schedule that each player would play at least once with every other player? I would appreciate any help that you can give me. Answered by Denis Hanson. |
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A worm on a hill |
2003-08-21 |
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From Lisa and Samantha: A WORM IS AT THE BOTTOM OF A 10 FOOT HILL. HE CRAWLS UP THE HILL 4 1/2 FEET A DAY. AT NIGHT WHEN HE REST HE SLIDES DOWN 2 1/2. HOW LONG DOES IT TAKE THE WORM TO CRAWL UP THE HILL. Answered by Penny Nom. |
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Two equations |
2003-08-21 |
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From Jennifer:
The following problems have me stuck and any help would be greatly appreciated seeing my text book is doing me no favours:
32a+1 - 28 3a + 9=0 and 52m - 5m=20 Answered by Penny Nom. |
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39 consecutive natural numbers |
2003-08-19 |
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From A student: Prove that among any 39 consecutive natural numbers it is always possible to find one whose sum of digits is divisible by 11. Answered by Penny Nom. |
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