parabola
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enTwo-faced conic sections
http://plus.maths.org/content/conic-sections
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Marianne Freiberger </div>
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<p>Play with our applets to explore the conic sections and their different definitions.</p>
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<p>What do the circle, the ellipse, the parabola and the hyperbola have in common? They are all shapes you get when you slice through a cone. You get a <strong>circle</strong> when you intersect a cone and a plane that is perpendicular to the cone's axis. When you tilt the plane slightly the circle turns into an <strong>ellipse</strong>. As you tilt the plane further, it will eventually become parallel to one of the <em>generating lines</em> of the cone — that's a straight line lying on the cone and emanating from the apex. When this happens the intersection is a <strong>parabola</strong>.<p><a href="http://plus.maths.org/content/conic-sections" target="_blank">read more</a></p>http://plus.maths.org/content/conic-sections#commentsconic sectionsellipsehyperbolaparabolaTue, 13 Jan 2015 12:25:48 +0000mf3446301 at http://plus.maths.org/contentRolling parabolically
http://plus.maths.org/content/rolling-parabollically
<p>Our good friend Julian Gilbey has just told us about an amazing fact: if you roll a parabola along a straight line then the shape its focus traces out as it goes is ... a catenary! That's the shape a chain makes when it hangs freely under gravity and also the shape that gives you the strongest arches (see <a href="http://www-history.mcs.st-and.ac.uk/Curves/Catenary.html">here</a> and <a href="http://plus.maths.org/content/maths-minute-st-pauls-dome">here</a> to learn more). </p><p><a href="http://plus.maths.org/content/rolling-parabollically" target="_blank">read more</a></p>http://plus.maths.org/content/rolling-parabollically#commentscatenaryparabolaMon, 17 Nov 2014 13:44:45 +0000mf3446137 at http://plus.maths.org/contentBridges, string art and Bézier curves
http://plus.maths.org/content/bridges-string-art-and-bezier-curves
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Renan Gross </div>
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The Jerusalem Chords Bridge, Israel, was built to make way for the city's light rail train
system. Its design took into consideration more than just utility — it is a work of
art, designed as a monument. Its beauty rests not only in the visual appearance of its criss-cross
cables, but also in the mathematics that lies behind it. So let's take a deeper look at it. </div>
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<h3>The Jerusalem Chords Bridge</h3>
<p>The Jerusalem Chords Bridge, Israel, was built to make way for the city's light rail train
system. However, its design took into consideration more than just utility — it is a work of
art, designed as a monument. Its beauty rests not only in the visual appearance of its criss-cross
cables, but also in the mathematics that lies behind it. Let us take a deeper look into these
chords.</p><p><a href="http://plus.maths.org/content/bridges-string-art-and-bezier-curves" target="_blank">read more</a></p>http://plus.maths.org/content/bridges-string-art-and-bezier-curves#commentsarchitectureBezier curveengineeringgeometrymathematics and artparabolaMon, 05 Mar 2012 09:31:51 +0000mf3445654 at http://plus.maths.org/contentDrinking coffee in the Klein Café
http://plus.maths.org/content/drinking-coffee-klein-cafeacute
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Jonathan Tims </div>
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<b>Runner up in the schools category</b>. Dusty books, chalky blackboards and checked shirts are all things usually associated with maths. But according to <b>Jonathan Tims</b>, pubs, hot chocolate and cats can be far more inspirational. Join him on a trip through shadow land. </div>
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<div class="pub_date">December 2006</div>
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<p style="color:purple;"><b><i>This article is a runner-up of the schools category of the Plus new writers award 2006.</i></b></p>
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<p>Dry and impenetrable?</p><p><a href="http://plus.maths.org/content/drinking-coffee-klein-cafeacute" target="_blank">read more</a></p>http://plus.maths.org/content/drinking-coffee-klein-cafeacute#comments41conic sectionsellipsegeometryhyperbolaPappus's theoremparabolaprojective geometrySat, 09 Dec 2006 00:00:00 +0000plusadmin2297 at http://plus.maths.org/content101 uses of a quadratic equation: Part II
http://plus.maths.org/content/101-uses-quadratic-equation-part-ii
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Chris Budd and Chris Sangwin </div>
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In issue 29 of <i>Plus</i>, we heard how a simple mathematical equation became the subject of a debate in the UK parliament. <b>Chris Budd</b> and <b>Chris Sangwin</b> continue the story of the mighty quadratic equation. </div>
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<div class="pub_date">May 2004</div>
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<p><i>In <a href="/issue29/features/quadratic/index.html">101 uses of a quadratic equation: Part I</a> in issue 29 of Plus we took a look at quadratic equations and saw how they arose naturally in various simple problems. In this second part we continue our journey. We shall soon see how the humble quadratic makes its appearance in many different and important applications.</i></p><p><a href="http://plus.maths.org/content/101-uses-quadratic-equation-part-ii" target="_blank">read more</a></p>http://plus.maths.org/content/101-uses-quadratic-equation-part-ii#comments30accelerationbernoulli equationchaosdifferential equationellipsegravitynavier-stokes equationsNewtonian mechanicsparabolapublic understanding of mathematicsquadratic equationFri, 30 Apr 2004 23:00:00 +0000plusadmin2248 at http://plus.maths.org/content