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.
Reasons for No Flowers on Crepe Myrtle. Nothing is more beautiful than the flowers on a crepe myrtle. However, a crepe myrtle not blooming can be frustrating. Here are some reasons why this happens and tips for getting crepe myrtle trees to bloom.