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Real Analysis

Real Analysis refers to the study of real valued functions. It particularly focuses on the properties of these functions, including but not limited to, the convergence and limits of sequences of real numbers, as well as the calculus of real numbers. In dealing with Real Analysis, it is important to understand the different terms. If a limit for a particular sequence exists, then the sequence is called convergent; however if the limit for a particular sequence does not exist, then the sequence is called divergent.

For example, if the sequence was 1, ½, 1/3 , ¼, 1/5, 1/6 and so on, this can be written in the following form:

(1/j)_j=1->inf

where,

j is the denominator of the function

inf is infinity

This sequence eventually converges to zero, because as j approaches infinity, the denominator gets extremely large, leaving the output of the function to be extremely small. However, the important aspect to consider is that the series never actually reaches zero, but it can get as infinitesimally close to it. This is why the study of limits in this particular context is considered under Real Analysis.

Categories within Real Analysis

Derivatives

Postings: 1,055

A Derivative is a measure of how the output of a specific function, which is not limited to y or f(x), changes with respect to the input.

Integrals

Postings: 1,928

An Integral is a function, F, which can be used to calculate the area bound by the graph of the derivative function, the x-axis, the vertical lines x=a and x=b.

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