Describe two ways in which mathematical notation is useful. Give an example in each case to demonstrate the benefits of your idea. For example, you might say that notation is useful because if a symbol is used to stand for something impossible to write down (for example, an infinite set or an infinite decimal expansion) then the power of this symbolism allows to denote something we otherwise wouldn't be able to. An example in this case would be the notation R which is used to denote the infinite set of all real numbers.