Anthony OR 柯志明
Classify quadrilaterals A to T. (Click a quadrilateral at the right, then click the quadrilaterals A to T in the same class.) Drag and rotate (the red point) the ruler to measure lengths and right angles.
Tess 2 step 4
The Gradient Vector and Directional Derivative
Animation of area under curve of f(x) and x-axis
Similar Triangles and Side Lenghts