The Rainier Valley (/reɪˈnɪər/ ray-NEER) is a district in southeast Seattle. It is located east of Beacon Hill; west of Mount Baker, Seward Park, and Leschi; south of the Central District and north of Rainier Beach. It is part of Seattle’s South End.
The derivative of a function of a single variable at a chosen input value, when it exists, is the slope of the tangent line to the graph of the function at that point.