Defining the cotangent function. The cotangent function is an old mathematical function. It was mentioned in 1620 by E. Gunter who invented the notation of cotangens. Later on J. Keill (1726) and L. Euler (1748) used this function and its notation in their investigations.
Crepe Myrtles are among the toughest, most adaptable, and showiest plants that can be grown in the Texas landscape. Along with their bright colorful bloom display during the summer months the leaves of the Crepe Myrtle also turn orange, red and yellow in the fall.
Whatever the total number of varieties, the important thing to remember is that you donât want to choose just by color. Gone are the days when we might ask for âa red crape myrtleâ or âa white one.â Gardeners have learned to ask for them by specific variety name so that they can better predict the plantâs performance.