In mathematics, a limit is a fundamental concept in calculus and mathematical analysis, describing the behavior of a function as its input approaches a particular value. Limits help in understanding what value a function (or sequence) approaches as the input gets closer and closer to some specific point.

Types of Limits:

1. Limit of a function: $\lim_{x \to a} f(x)$ This describes the value that $f(x)$ approaches as $x$ approaches $a$. For example: $\lim_{x \to 2} (3x + 1) = 7$ means that as $x$ gets closer to 2, $3x + 1$ gets closer to 7.

2. One-sided limits:

   • Left-hand limit: $\lim_{x \to a^-} f(x)$ where $x$ approaches $a$ from the left (values less than $a$).
   • Right-hand limit: $\lim_{x \to a^+} f(x)$ where $x$ approaches $a$ from the right (values greater than $a$).

3. Limits at infinity: Describes the behavior of a function as the input $x$ grows without bound (either positively or negatively): $\lim_{x \to \infty} f(x) \quad \text{or} \quad \lim_{x \to -\infty} f(x)$

4. Infinite limits: When a function grows without bound as $x$ approaches a particular value, it’s written as: $\lim_{x \to a} f(x) = \infty$

5. Limits in sequences: These represent the behavior of a sequence $a_n$ as $n$ approaches infinity: $\lim_{n \to \infty} a_n$

Example: Limit of a function

Consider the function $f(x) = \frac{2x^2 - 1}{x - 1}$. To find $\lim_{x \to 1} f(x)$, you would check if substituting $x = 1$ gives a defined value. If it doesn’t, you can simplify the expression or use other techniques like factoring or L'Hopital's Rule.

Would you like a more detailed explanation on a specific type of limit or how to solve limit problems?

---

Here are 5 related questions to expand on this topic:

1. What is the difference between finite and infinite limits?
2. How do you solve limits using L'Hopital's Rule?
3. What are discontinuities in limits and how do they affect limit calculations?
4. How do you calculate one-sided limits for piecewise functions?
5. What are some practical applications of limits in physics and engineering?

Tip: Always check whether a function is continuous at a point before finding its limit. If it’s not, consider one-sided limits.