Radian symbol, and in mathematical writing the symbol "rad" is almost always omitted. When quantifying an angle in the absence of any symbol, radians are assumed, and when degrees are meant the symbol ° is used. It follows that the magnitude in radians of one complete revolution (360 degrees) is the length of the entire circumference divided by the radius, or , or 2. Thus 2 radians is equal to 360 degrees, meaning that one radian is equal to 180/ degrees. The relation formula_1 can be derived using the formula for arc length. Taking the formula for arc length, or formula_2.
Six Degrees patent Zynga and Tribe.net for $700,000 at an auction in 2003. When explaining his reasoning for purchasing the Six Degrees patent, Hoffman stated, "Right now you're hearing a lot of spurious patent threats (...) And that's why I moved quickly to get a patent that was foundational." He also commented on other entrepreneurs' views of social networking: "The general attitude among entrepreneurial people is that they think that they were first and that there is no history to what they are doing (...) Both Mark and I had tracked six degrees as an intellectual precursor to our own businesses." Andrew Katz