The principal part at of a function
is the portion of the Laurent series consisting of terms with negative degree. That is,
is the principal part of at . has an essential singularity at, if and only if the principal part is an infinite sum.
Famous quotes containing the words principal and/or part:
“The principal thing children are taught by hearing these lullabies is respect. They are taught to respect certain things in life and certain people. By giving respect, they hope to gain self-respect and through self-respect, they gain the respect of others. Self-respect is one of the qualities my people stress and try to nurture, and one of the controls an Indian has as he grows up. Once you lose your self-respect, you just go down.”
—Henry Old Coyote (20th century)
“Helping children at a level of genuine intellectual inquiry takes imagination on the part of the adult. Even more, it takes the courage to become a resource in unfamiliar areas of knowledge and in ones for which one has no taste. But parents, no less than teachers, must respect a child’s mind and not exploit it for their own vanity or ambition, or to soothe their own anxiety.”
—Dorothy H. Cohen (20th century)