BRAIN TEASERS

enter your answer and press button OK

Find number abc

If c4bb2 + 4cbc4 = 1aa1a6 find number abc.

Correct answers: 67

The first user who solved this task is Djordje Timotijevic.

#brainteasers #math

Register with your Google Account and start collecting points.

Check your ranking on list.

Pain makes you stronger

Pain makes you stronger.

Jokes of the day - Daily updated jokes. New jokes every day.

Follow Brain Teasers on social networks

Brain Teasers

puzzles, riddles, mathematical problems, mastermind, cinemania...

Camera obscura

In 1544, a solar eclipse was viewed at Louvain, which was later depicted in the first published book illustration of the camera obscura in use. Dutch mathematician and astronomer Reinerus Gemma-Frisius viewed a solar eclipse using a hole in one wall of a pavillion to project the sun's image upside down onto the opposite wall. He published the first illustrationof a camera obscura, depicting his method of observation of the eclipse in De Radio Astronomica et Geometrica (1545). Several astronomers made use of such a device in the early part of the 16th century. Both Johannes Kepler and Christopher Scheiner used a camera obscura to study the activity of sunspots. The technique was known to Aristotle (Problems, ca 330 BC).

This site uses cookies to store information on your computer. Some are essential to help the site properly. Others give us insight into how the site is used and help us to optimize the user experience. See our privacy policy.