The Y doesn't stand for anything. It is part of the word RAY. In fact, the X doesn't stand for anything either. They were called x-rays because the type of radiation was unkno â¦ wn at the time. is added to make the name sound better. Megaman X, Sonic X, etcetera. It could stand for Extreme or something but that's looking a bit t â¦ oo much into it. 1  Cancers: X-Ray Identification of a Sarcoma Tumor In orthopedics, cancer is a serious issue because of the metastatic nature of cancerous malignancies.
Calculus is the study of how things change. It provides a framework for modeling systems in which there is change, and a way to deduce the predictions of such models. I have been around for a while, and know how things change, more or less.
Differential calculus. In mathematics, differential calculus is a subfield of calculus concerned with the study of the rates at which quantities change. It is one of the two traditional divisions of calculus, the other being integral calculus. The primary objects of study in differential calculus are the derivative of a function, related notions such as the differential, and their applications. The derivative of a function at a chosen input value describes the rate of change of the function near that input value. The