$$ \int_{a}^{b} \frac{e^{-x^2}}{\sqrt{1 + (\frac{d}{dx} \arctan(x))^2}} dx = \frac{\pi}{2} $$ This formula combines several mathematical concepts: * **Integration:** The symbol ∫ represents the definite integral of a function over a specific interval [a, b]. * **Exponential Function:** The term $e^{-x^2}$ represents an exponential function where the exponent is a squared term. * **Arctangent Function:** $\arctan(x)$ is the inverse tangent function, also known as arctan. * **Derivative:** The expression $\frac{d}{dx} \arctan(x)$ denotes the derivative of the arctangent function with respect to x. * **Square Root:** The √ symbol indicates the square root of a complex expression involving trigonometric functions. Let me know if you'd like me to elaborate on any particular part of this formula!