Amaze and delight others as you multiply, divide, and square at lightning fast speed. Learn and practice the tricks of mental math calculation in a fun and engaging application. Study any of the math tricks and then practice them as you progress through various levels of proficiency. Tease your brain with a quick practice session while waiting in lines, riding in the car, or on the plane. Only the basic math skills of addition, subtraction and simple multiplication and division are needed to achieve astonishing results. Students: Baffle your math teachers by providing answers faster than thought possible. Teachers: Inspire your students as you pull answers to math problems out of thin air.
Tai Chi Push Hands with Huang Sheng Shyan and Tony Ward 0:37 Wee Kee Jin! Thanx Gerhard Dänekamp for the hint!
This is a demonstration of my ifs-editor. There’s no sound. It’s just a capture of my desktop. The translucent pink or blue blocks are the affine transformations. The handles appear when you click on one. The dark blue handle lets you move it. The purple one rotates and scales. The orange one is free, so you can even reverse the orientation (which is what makes the block pink or blue). You can also edit the transformation numerically with the edit button below the text area. (x0, y0) is the offset of the blue handle, (a,c) is the vector from the blue handle to the purple handle. (b,d) is the vector from the blue handle to the orange handle. The fixed square outline on the drawing screen is just for reference. The lower left shows a rough preview of the fractal. The clear button erases all the blocks. The add button creates a new block. The delete button deletes the currently selected block. Load & save is for loading and saving the blocks to a file. Sketch opens a window with a finer-detail sketch of the fractal. Render lets you create a .png file of the fractal. When using render, you sometimes have to increase the maximum recursion depth. If it’s too high, the image may take a very long time to draw. If it’s too low, you may end up with some big clunky blocks in the final image. The video goes through a few different values of this setting to show the difference.