What is bounded and unbounded?

Bounded and unbounded high numbers refer to the desirable range of the domain and value of a function.

If there is always │f(x)│≤M for all x values belonging to an interval I, where m is a constant that has nothing to do with x, then we say that f(x) is bounded in the interval I, otherwise it is called unbounded.

For example, y=arctanx is bounded on the whole real number field.

You can visually find two boundaries, one is y=π/2, and the other is y=-π/2. All the function values are outside this range.

If a function has a minimum and a maximum, it must be bounded.

The maximum and minimum values are boundaries.

The most vivid image of unbounded function is y=tanx. When x approaches π/2, the function value approaches infinity.