Reflections about the maths daily in the world around us.
The nummolt - mathcats materials, the mathematics behind them and related to them.
Math education and apps.
Primes as the basic building blocks of numbers
It
focuses on graphically showing the idea of proportion, and the
equivalent fractions for solving directly proportional problems.
Attempts to show what is routinely done with cross multiplication.Shows
the slope, the ratio, the proportion between two numbers, and allows
applying that proportion to other numbers, whether they are greater or
less than the initial one.
Graphically the proportion is fixed with the red bars.
The blue dot slides down the slope fixed by the proportion
Math Garden + In this app, natural numbers are represented as vegetables (plants):
Each number is a graph tree with prime factors in the nodes.
Plants similar to: Dandelions, (from French: 'dent-de-lion')
Seeds fall from the sky They should be planted. And then grow the plant corresponding to the seed (and the number chosen).
When the plant is plucked from the ground, dandelions return to the sky.
When two seeds overlap on the ground they add up.
When two buried seeds overlap, they multiply.The result of the multiplications does not depend on the order of their superposition.But different arrangements make trees with different shapes.
The different possible shapes of 105:
(3*5*7; 3*7*5; 5*3*7; 5*7*3; 7*3*5; 7*5*3)
The app allows to add, subtract, multiply and divide whole numbers.And you can also add, multiply and divide rational numbers.Rational numbers are made in the Fraction Building Tool on the left.
In a mirror anamorphosis, a conical or cylindrical mirror
is placed on the distorted drawing or painting to reveal an undistorted
image. The deformed picture relies on laws regarding angles of
incidence of reflection.
The app (Conic Anamorphism Cameras) has 2 type of cameras:
1.- For to build a conical anamorphosis,
2.- for to reveal the undistorted image.
Image distortion and reconstruction can be performed using 9 different angles of cone:
From 41.4º to 75.5º :
(An undistorted triangle is a trifolium)
Some examples made with the app:
Thonet Chair:
Undistorted Thonet Chair:
Cage Bird:
Cage Bird Conical Anamorphism with center in the yellow bird:
