Parametric Sketches

Tuesday, 24 April 2018

3:03 PM

A curve in cartesian form  can be written parametrically as

 

 

Machine generated alternative text:
The table below lists some commonly used parametrisations of conic sections. 
Conic section Cartesian equation Parametric equation 
btant 
Parabola 
Circle 
Ellipse 
Hyperbola 
2 
4ay = x 
2 
2 
1 
2 
a 
2 
a 
b2 
x(t) 
2at 
at2 
— a cos t 
y(t) — 
— asin t 
a cos t 
y(t) 
b sin t 
a sec t

Machine generated alternative text:
Sketching parametrically defined curves 
We shall use some of the same ideas as we did in sketching curves given explicitly. 
o 
o 
o 
o 
o 
The domain refers to t and now range of x(t) gives x extent of the graph; 
range of gives y extent of graph; 
The x-intercepts are given by = 0, and the y-intercepts by = 0; 
Look for asymptotes; 
Locate any "nasty" points in the graph, mainly where x' (t) 0; 
Find where the graph has positive or negative slope.

 

 

Created with Microsoft OneNote 2016.