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What is an envelope?

Published online by Cambridge University Press:  22 September 2016

J.W. Bruce  and
P.J. Giblin
J.W. Bruce
Affiliation:
Dept. of Mathematics, University College, Cork, Ireland
P.J. Giblin
Affiliation:
Dept. of Pure Mathematics, University of Liverpool, P.O. Box 147, Liverpool L69 3BX
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Extract

If we draw a lot of circles centred on the x-axis and all having radius 1, as in the diagram, then the eye picks out the horizontal lines y = ± 1 running along the tops and bottoms of the circles.

Information

Type
Research Article
Information
The Mathematical Gazette , Volume 65 , Issue 433 , October 1981 , pp. 186 - 192
Copyright
Copyright © Mathematical Association 1981

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References

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