The National Geographic Society is an organization started by Alexander Graham Bell in 1888. Its purpose is to advance the general knowledge of geography and the world among the general public. To this end, it sponsors exploration, and publishes a monthly magazine, National Geographic. It was founded on January 27, 1888 in Washington, DC.
... terms of the coefficients a, b and c, which are assumed to be real (but see below for generalizations) with a being non-zero. These solutions are also called the ...