Part 1 : Internet - commonly used resources

1. Differentiation (Step by step)
http://www.calc101.com/webMathematica/derivatives.jsp

2. Indefinite integral
http://integrals.wolfram.com/index.jsp

3. Definite integral
http://www.webmath.com/nintegrate.html

4. Probability calculator
http://www.psychstat.missouristate.edu/pdf/pdfj.htm

5. Building houses (3D figure and orthographic projection)
http://www.fi.uu.nl/toepassingen/00249/toepassing_wisweb.en.html

More

Part 2 : Software - Geogebra

Official site
Download Geogebra
User Guide

Dynamic geometry + Alegrabic computation + Calculus (~ Mixture of SketchPad and Winplot) ***Better than Winplot: demonstrate dynamic geometry ***Better than SketchPad: free and files can be saved Not bad graphical output Can create web-based file Disadvantage: tell you later...:P

Basic examples
Miquel Theorem (Dynamic)
Perpendicular (Basic construction)
Reflection (Basic transformation)
Sector (Graphic output)
Integral (Integration, graphic output and text)
Basic Quadratic Curve (Demonstration, changing parameters)
Family of circle (Coordinate system, checking answer)
Curve Sketching (Tangent, graphic output)
...
You may download the above 8 files by saving and unzipping the zip file here.

More examples posted in my forum
Graph of y = f(|x|)
F.4 General Mathematics : Transformation of function
Proof without words

To learn more about Geogebra and other mathematics softwares, please visit the webpage written by Mr. Arthur Lee Man Sang.

Reminders:
1. You may download the software in my open drive (p:\nwc\math\Geogebra\GeoGebra-2.7.1.0.exe).
2. To download individual Geogebra files, you should type the extension .ggb (instead of .zip).
3. Resize the window to "best fit" before exporting the ggb file into png figure.
4. The HELP file is helpful and there's a user's forum in the official site.

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