[alogo] Example of use of the tool [Length-Gauge]

In this example we construct the graph of the function y = 4/(1+x^2), using the tool of [Geometric-Locus] (4th button from below).

1) Construct first line BC.
2) Put a point D on this line.
3) Select the tool [Measures \ Length-Gauge _ _] and a) click on the line BC, b) click on point D. This constructs the label [x = ...] displaying the ratio BD/CD.
4) Double-click on label [x = ...] holding simultaneously down the key Ctrl. This defines point Z on the x-axis, representing the value of the label [x = ... ].
5) Somewhere in the white space type the text: formula y = 4/(1+x^2)
6) While this text box is selected press the key Enter. This creates the corresponding formula-object (that with the blue box).

[0_0] [0_1] [0_2] [0_3]
[1_0] [1_1] [1_2] [1_3]

7) Right click on the formula object and select the menu-item [Activate].
8) Then click on label [x = ...] . This produces the label [y = ... ].
9) Double click on label [y = ... ] holding down the key F2. This defines point H on y-axis, representing the value of label [y = ... ].
10) Select the tool [Quadrangles \ Screen-Rectagle]. Click on H ...drag ... release at Z. This defines the rectangle with diagonal HZ.
11) Select the tool of [Geometric-Locus] (4th button from below). Click on D and then click on E. This produces the graph of the function.

Produced with EucliDraw©