Explaining, convincing and proving

  • Polynomial Relations
    problem
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    Polynomial Relations

    Age
    16 to 18
    Challenge level
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    Given any two polynomials in a single variable it is always possible to eliminate the variable and obtain a formula showing the relationship between the two polynomials. Try this one.
  • How Many Solutions?
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    How Many Solutions?

    Age
    16 to 18
    Challenge level
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    Find all the solutions to the this equation.
  • There's a limit
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    There's a Limit

    Age
    14 to 18
    Challenge level
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    Explore the continued fraction: 2+3/(2+3/(2+3/2+...)) What do you notice when successive terms are taken? What happens to the terms if the fraction goes on indefinitely?
  • Common Divisor
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    Common Divisor

    Age
    14 to 16
    Challenge level
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    Find the largest integer which divides every member of the following sequence: 1^5-1, 2^5-2, 3^5-3, ... n^5-n.
  • Quadratic Harmony
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    Quadratic Harmony

    Age
    16 to 18
    Challenge level
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    Find all positive integers a and b for which the two equations: x^2-ax+b = 0 and x^2-bx+a = 0 both have positive integer solutions.
  • Rule of Three
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    Rule of Three

    Age
    11 to 14
    Challenge level
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    If it takes four men one day to build a wall, how long does it take 60,000 men to build a similar wall?
  • Unit Interval
    problem
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    Unit Interval

    Age
    14 to 18
    Challenge level
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    Take any two numbers between 0 and 1. Prove that the sum of the numbers is always less than one plus their product?
  • Power Quady
    problem
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    Power Quady

    Age
    16 to 18
    Challenge level
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    Find all real solutions of the equation (x^2-7x+11)^(x^2-11x+30) = 1.
  • Shape and territory
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    Shape and Territory

    Age
    16 to 18
    Challenge level
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    If for any triangle ABC tan(A - B) + tan(B - C) + tan(C - A) = 0 what can you say about the triangle?
  • Binomial
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    Binomial

    Age
    16 to 18
    Challenge level
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    By considering powers of (1+x), show that the sum of the squares of the binomial coefficients from 0 to n is 2nCn