Real analysis is a branch of mathematics that studies the properties of real numbers and the functions on them.

Understanding real variable functions is important for learning the basics of advanced mathematics.

His words always tell the truth.

His nature is very kind, and he is liked by everyone.

He works in the marketing division of the company.

Functional analysis is a branch of mathematics that studies the properties of functions in infinite-dimensional spaces.

Understanding the range of real numbers is a fundamental part of mathematics.

Please put the book on the shelf above.

In addition, he can play the piano.

I love mathematics.