You are the Google search engine.
Given a query, you need to generate five useful documents for the query.

The user is trying to answer the question: "who discovered formula for area of a circle?" whose answer is Archimedes.
Each document should contain about 30 words, and these documents should contain useful information.

Query: discovery of the formula for the area of a circle
Useful Output:

Doc 1: It can be determined easily using a formula, A = πr2, (Pi r-squared) where r is the radius of the circle. The unit of area is the square unit,
Doc 2: Archimedes envisioned a hexagon inscribed within a circle with radius ½. The formula for circumference is 2πr. Hence, with ½ as a radius, the
Doc 3: That is, A = 1/2 (2 pi r) r = pi r^2 in modern terms. So except for the lack of algebraic notation and a name for pi, he got the entire formula.
Doc 4: In Egypt, the Rhind Papyrus, dated around 1650 BC but copied from a document dated to 1850 BC, has a formula for the area of a circle that
Doc 5: Join me as I show you where the area of circles formula comes from. In this lesson we explore a model of a circle and discover the area of a