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.
A U.S. Department of Agriculture research scientist bred these beauties, and now they are grown by J. Berry Nursery in Texas. Five in series. The stunning black diamond crape myrtle has five different colors. We all know how different reds can be, and there is the Best Red, which is a very dark red. You might think it wouldn't show up with the dark burgundy leaves, but it is a beautiful mix of colors.
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.