Limits

  • There's a limit
    problem
    Favourite

    There's a Limit

    Age
    14 to 18
    Challenge level
    filled star empty star empty star
    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?
  • Exponential Trend
    problem
    Favourite

    Exponential Trend

    Age
    16 to 18
    Challenge level
    filled star empty star empty star
    Find all the turning points of y=x^{1/x} for x>0 and decide whether each is a maximum or minimum. Give a sketch of the graph.
  • Discrete Trends
    problem
    Favourite

    Discrete Trends

    Age
    16 to 18
    Challenge level
    filled star filled star empty star
    Find the maximum value of n to the power 1/n and prove that it is a maximum.
  • Spokes
    problem
    Favourite

    Spokes

    Age
    16 to 18
    Challenge level
    filled star filled star filled star
    Draw three equal line segments in a unit circle to divide the circle into four parts of equal area.
  • The silhouette of a cartoon witch.
    problem
    Favourite

    Witch of Agnesi

    Age
    16 to 18
    Challenge level
    filled star empty star empty star

    Sketch the members of the family of graphs given by $y = a^3/(x^2+a^2)$ for $a=1, 2$ and $3$.

  • Converging Product
    problem
    Favourite

    Converging Product

    Age
    16 to 18
    Challenge level
    filled star filled star empty star
    In the limit you get the sum of an infinite geometric series. What about an infinite product (1+x)(1+x^2)(1+x^4)... ?
  • Rain or Shine
    problem
    Favourite

    Rain or Shine

    Age
    16 to 18
    Challenge level
    filled star filled star empty star

    Predict future weather using the probability that tomorrow is wet given today is wet and the probability that tomorrow is wet given that today is dry.

  • Reciprocal Triangles
    problem

    Reciprocal Triangles

    Age
    16 to 18
    Challenge level
    filled star filled star empty star
    Prove that the sum of the reciprocals of the first n triangular numbers gets closer and closer to 2 as n grows.
  • Lower Bound
    problem

    Lower Bound

    Age
    14 to 16
    Challenge level
    filled star filled star empty star
    What would you get if you continued this sequence of fraction sums? 1/2 + 2/1 = 2/3 + 3/2 = 3/4 + 4/3 =
  • Golden Eggs
    problem

    Golden Eggs

    Age
    16 to 18
    Challenge level
    filled star filled star empty star
    Find a connection between the shape of a special ellipse and an infinite string of nested square roots.