Mathematics
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The yupana ( Quechua for "counting tool") is a device used by the Incas , presumably as a type of calculator . Though some researchers have hypothesized how this implement might function like an abacus , [ 1 ] [ 2 ] others are less certain that it was used for this purpose. [ 3 ] The 16th-century account of Spanish priest José de Acosta suggests that Incas may have possessed such a device: [...] to see them use another kind of calculator, with maize kernels. In order to carry out a very difficult computation for which an able computer would require pen and paper, these Indians make use of their kernels. They place one here, three somewhere else and eight. They move one kernel here and there and the fact is that they are able to complete their computation without making the smallest mistake. as a matter of fact, they are better at practical arithmetic than we are with pen and ink.
Yupana - an Incan Fibonacci Calculator
emergence
fractals
Geometry
Science Mysteries, Fibonacci Numbers and Golden section in Nature
Golden Ratio & Golden Section : : Golden Rectangle : : Golden Spiral Golden Ratio & Golden Section In mathematics and the arts, two quantities are in the golden ratio if the ratio between the sum of those quantities and the larger one is the same as the ratio between the larger one and the smaller. Expressed algebraically: The golden ratio is often denoted by the Greek letter phi (Φ or φ).
December 2009 Think drug-induced hallucinations, and the whirly, spirally, tunnel-vision-like patterns of psychedelic imagery immediately spring to mind. But it's not just hallucinogenic drugs like LSD, cannabis or mescaline that conjure up these geometric structures. People have reported seeing them in near-death experiences, as a result of disorders like epilepsy and schizophrenia, following sensory deprivation, or even just after applying pressure to the eyeballs. So common are these geometric hallucinations, that in the last century scientists began asking themselves if they couldn't tell us something fundamental about how our brains are wired up.
Uncoiling the spiral: Maths and hallucinations
Evolution of the limit cycle in the phase plane. Notice the limit cycle begins as circle and, with varying μ , become increasingly sharp. An example of a Relaxation oscillator .
Van der Pol oscillator
9 Mental Math Tricks
Math can be terrifying for many people. This list will hopefully improve your general knowledge of mathematical tricks and your speed when you need to do math in your head. 1. Multiplying by 9, or 99, or 999 Multiplying by 9 is really multiplying by 10-1.GNU Octave is a high-level interpreted language, primarily intended for numerical computations. It provides capabilities for the numerical solution of linear and nonlinear problems, and for performing other numerical experiments. It also provides extensive graphics capabilities for data visualization and manipulation.
Octave
See Math tricks on video at the Wild About Math! mathcasts page. Being able to perform arithmetic quickly and mentally can greatly boost your self-esteem, especially if you don't consider yourself to be very good at Math. And, getting comfortable with arithmetic might just motivate you to dive deeper into other things mathematical. This article presents nine ideas that will hopefully get you to look at arithmetic as a game, one in which you can see patterns among numbers and pick then apply the right trick to quickly doing the calculation.
Impress your friends with mental Math tricks » Fun Math Blog
An Intuitive Explanation of Fourier Theory
Steven Lehar slehar@cns.bu.edu Fourier theory is pretty complicated mathematically. But there are some beautifully simple holistic concepts behind Fourier theory which are relatively easy to explain intuitively. There are other sites on the web that can give you the mathematical formulation of the Fourier transform.