Calculating Integral E X 2
The integral of e^x^2 is a fundamental calculation in calculus that appears in probability, physics, and engineering. This guide explains how to compute it, provides a working calculator, and includes practical examples.
What is the integral of e^x^2?
The integral of e^x^2 is expressed as:
Where:
- erf(x) is the error function, defined as erf(x) = (2/√π) ∫₀ˣ e^(-t²) dt
- C is the constant of integration
The error function is a special function that cannot be expressed in terms of elementary functions, so the integral of e^x^2 is typically left in terms of erf(x).
How to calculate the integral of e^x^2
Step-by-step method
- Recognize that the integral of e^(x²) is not elementary and requires special functions.
- Use integration by parts or substitution to express the integral in terms of the error function.
- Recall the standard result: ∫ e^(x²) dx = (√π/2) * erf(x) + C
- Apply the limits of integration if definite integral is required.
Assumptions and limitations
The integral of e^x^2 is an improper integral that converges to infinity at both ±∞. The error function erf(x) is defined for all real x and has the following properties:
- erf(0) = 0
- erf(∞) = 1
- erf(-x) = -erf(x)
Note: The integral of e^x^2 cannot be expressed in terms of elementary functions. The error function is the standard way to represent this integral.
Examples of calculating the integral of e^x^2
Example 1: Indefinite integral
Calculate ∫ e^(x²) dx
Solution:
Example 2: Definite integral from 0 to 1
Calculate ∫₀¹ e^(x²) dx
Solution:
Numerical approximation: erf(1) ≈ 0.8427, so the result is approximately 0.8862.
FAQ
Is the integral of e^x^2 elementary?
No, the integral of e^x^2 cannot be expressed in terms of elementary functions. It requires the error function erf(x).
What is the error function erf(x)?
The error function erf(x) is defined as erf(x) = (2/√π) ∫₀ˣ e^(-t²) dt. It is a special function that appears in probability, statistics, and physics.
How do I compute the integral of e^x^2 numerically?
For numerical computation, you can use the error function approximation or numerical integration methods. The calculator on this page provides a convenient way to compute the integral.