|Maryam Mirzakhani was the first woman to receive the Fields Medal. The Fields Medal is often called the "Nobel Prize of mathematics", but it is only awarded every four years and only to someone younger than 40 years old. Here is a short video about her and her work.|
|July is the month in which chemist Stephanie Kwolek was born (July 31, 1923). In 1965, Kwolek invented Kevlar, the lightweight fiber used in bulletproof vests. Her invention has saved thousands of lives. Kevlar is also used in airplanes, mobile phones, and sailboats. Kwolek is the only female employee of DuPont to be awarded the company's Lavoisier Medal for outstanding technical achievement. Antoine Lavoisier is known as the "Father of Modern Chemistry." He was guillotined during France's Reign of Terror. His good friend was the mathematician Joseph-Louis Lagrange who famously said, "It took them only an instant to cut off this head, and one hundred years might not suffice to reproduce its like." Lagrange survived the French Revolution and is buried in the Panthéon in Paris.|
|July is also the month in which the mathematician Gottfried Leibniz was born (July 1, 1646). Self-taught in mathematics, Leibniz developed calculus independently of Isaac Newton. His notation was superior to Newton's and is still in use today. Leibniz is credited with introducing the dot for multiplication. In a letter to Johann Bernoulli, he wrote, "I do not like X as a symbol for multiplication, as it is easily confounded with x..."|
|Speaking of Johann Bernoulli, he too was born in July (July 27, 1667 Julian calendar). The Bernoulli family is the most famous family of mathematicians in history. There was a big rivalry between Johann and his mathematician older brother Jakob. Johann had three mathematician children: Daniel, Nicolaus, and Johann II. Johann was an early pioneer of calculus. He once posed two difficult problems that Isaac Newton solved immediately. Newton sent in his solutions anonymously, but Bernoulli recognized Newton's work and is reported to have said, "We know the lion by his claw."|
|The Heat Index (HI) is a measure of how hot it really feels when the effect of humidity is added to the temperature. The formula to calculate the heat index uses many algebra concepts including positive and negative exponents and scientific notation.
HI = -42.379 + 2.04901523T + 10.14333127H - 0.22475541TH - 6.83783×10-3T2 - 5.481717×10-2H2 + 1.22874×10-3T2H + 8.5282×10-4TH2 - 1.99×10-6T2H2
where T = temperature (°F) and H = relative humidity (%). For example, if it is 90°F and the humidity is 90%, it feels like 122°F.
World Language students, try reading this site in Spanish or French.