MATH 131 -- Calculus for Physical and Life Sciences 

The cycloids 

September 17, 2007 

 

The cycloids are the curves given by the parametric equations 

 

  Typesetting:-mrow(Typesetting:-mi(   

 

If  Typesetting:-mrow(Typesetting:-mi(, the curve is an (ordinary) cycloid; if  a > b, the curve 

is called a curtate cycloid;  if  a < b,  the curve is called a  

prolate  cycloid. 

 

Here are the shapes.  First  a = b = 1 

 

> plot([`+`(t, `-`(sin(t))), `+`(1, `-`(cos(t))), t = 0 .. `+`(`*`(4, `*`(Pi)))]); 1
 

Plot_2d
 

 

Next,  Typesetting:-mrow(Typesetting:-mi( 

> plot([`+`(t, `-`(`*`(`/`(2, 3), `*`(sin(t))))), `+`(1, `-`(`*`(`/`(2, 3), `*`(cos(t))))), t = 0 .. `+`(`*`(4, `*`(Pi)))], x = 0 .. `+`(`*`(4, `*`(Pi))), y = 0 .. 2); 1
 

Plot_2d
 

 

Finally,  Typesetting:-mrow(Typesetting:-mi( 

> plot([`+`(t, `-`(`*`(`/`(3, 2), `*`(sin(t))))), `+`(1, `-`(`*`(`/`(3, 2), `*`(cos(t))))), t = 0 .. `+`(`*`(4, `*`(Pi)))]); 1
 

Plot_2d
 

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