# Convergence articles

Displaying 411 - 420 of 723

In Archimedes' Book of Lemmas (ca 250), he introduces a figure that, due to its shape, has historically been known as "the shoemaker's knife" or arbelos.

What is the perpendicular height of a cloud when its angles of elevation were 35 degrees and 64 degrees as taken by two observers at the same time...

There are a number of wonderful mathematics websites that readers of Convergence should be aware of. We describe some of them here.

A comprehensive history of trigonometry from ancient times to the Renaissance.

A general formed his men into a square, that is, an equal number in rank and file, and he found that he had an excess of 59 men.

Show that the curves x2 - y2 = a2 and 2 xy = b2 cross at right angles.

A man entered an orchard through 7 gates, and there took a certain number of apples. When he left the orchard, he gave the first guard half the apples he had and 1 apple more.

A historically minded textbook designed to teach real analysis by considering some of the problems faced by 19th century mathematicians.

To find three quantities x.y, and z...

The cavity of our chimney is an upright parallelepiped, the diagonal of whose base is 60"; and the height of the lower side of the lintel above the plane of the floor is 40".