Limits

There are 20 NRICH Mathematical resources connected to Limits
Converging Product
problem
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Converging product

Age
16 to 18
Challenge level
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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
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Rain or shine

Age
16 to 18
Challenge level
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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.
There's a limit
problem
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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?
Witch of Agnesi
problem
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Witch of agnesi

Age
16 to 18
Challenge level
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Sketch the members of the family of graphs given by y = a^3/(x^2+a^2) for a=1, 2 and 3.
Discrete Trends
problem
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Discrete trends

Age
16 to 18
Challenge level
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Find the maximum value of n to the power 1/n and prove that it is a maximum.
Exponential Trend
problem
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Exponential trend

Age
16 to 18
Challenge level
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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.
Spokes
problem
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Spokes

Age
16 to 18
Challenge level
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Draw three equal line segments in a unit circle to divide the circle into four parts of equal area.
Over The Pole
problem

Over the pole

Age
16 to 18
Challenge level
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Two places are diametrically opposite each other on the same line of latitude. Compare the distances between them travelling along the line of latitude and travelling over the nearest pole.
Triangle Incircle Iteration
problem

Triangle incircle iteration

Age
14 to 16
Challenge level
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Keep constructing triangles in the incircle of the previous triangle. What happens?
Reciprocal Triangles
problem

Reciprocal triangles

Age
16 to 18
Challenge level
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Prove that the sum of the reciprocals of the first n triangular numbers gets closer and closer to 2 as n grows.