Question

Plz explain that what is delta of lowercase

Answer 1

Often the upper case delta is used to represent a difference between two quantities. For example, the slope of a line is Δy/Δx = (y2-y1)/(x2-x1). The symbol can often be read as the word "change" as in, "change in y divided by change in x".

The lower case delta is often used to represent the infinitesimal change much of calculus is based on.