GUATEMALA CITY - Torrential rains brought by the first tropical storm of the 2010 season pounded Central America and southern Mexico, triggering deadly landslides. The death toll stood at 15 Sunday but authorities said the number could rise.
Archimedes proved the formula for the area of a circle (A = Ï r 2, where r is the radius of the circle) and showed that the value of Ï lay between 3 + 1/7 (approximately 3.1429) and 3 + 10/71 (approximately 3.1408).
X means any number. E means is an Element of. R means the set of Real numbers. For the domain and range...it depends on which function you use to draw the circle. Only functions have domain and range. If you use a polar function, which uses angle and radius instead of X and Y, you could draw a circle by saying f(t)= r*pi*t, where t is the angle.