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Graph

Some ideas of transformations are illustrated. Omnigraph has been used for the displays but the principles apply to any graphing program.
The y=f(cx) transformation
The y=cf(x) transformation
The y=f(x)+c transformation
The y=f(x+c) transformation
Gradient
Rational polynomials
Lissajou figures

Mainpage
Graphs


The y=f(cx) transformation

The curve y = (cx)²+(cx)-1 is displayed for various values of c. As c is increased the curve contracts horizontally. This stretching has scale factor 1/c.

omnanim1.gif

The y=cf(x) transformation

The curve y = c(x²+x-1) is displayed for various values of c. As c is decreased the curve is stretched vertically. The stretch has scale factor c.

omnanim1.gif

The y=f(x)+c transformation

The curve y = x²+x+c is displayed for various values of c.
As c is increased the curve is translated vertically upwards.

omnanim3.gif

The y=f(x+c) transformation

The curve y = (x+c)²+(x+c)-1 is displayed for various values of c.
As c is increased the curve is translated horizontally to the left.

omnanim3.gif

Gradient

Tangents drawn at various points along a cubic curve show how the gradient changes.


animated tangent lines

Rational polynomials

The curve of the graph y=1/(x2+c) has either three parts, two parts or one part, depending on the value of the constant c. This animation shows the curve for values increasing from -0.9 through zero to 0.5:


animated rational polynomial

Lissajou figures

Parametric equations of the form x=sin(f(t)), y=cos(f(t)) produce lissajou figures. Here is a display of one simple case based on x=sin(ct), y=cos(t) for c varying between 1 and 2.


These animations were produced by GIF Construction Set, which can be downloaded from Alchemy.



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