Evaluating the Integral x Cubed Over e^x Minus 1

This animation walks through the classic improper integral ∫₀^∞ x³/(e^x − 1) dx, showing how expanding 1/(e^x − 1) as a geometric series turns the problem into a sum of standard Gamma-function integrals. Step by step, it connects the result to the Riemann zeta function ζ(4) and the Gamma function Γ(4), arriving at the closed form π⁴/15. Useful for university students studying advanced calculus, special functions, or the physics of blackbody radiation.

Narrated · 16:9 · Preview before teaching · automatic layout checks do not establish subject accuracy

The prompt that made it

Solve this advanced calculus problem: Evaluate ∫₀^∞ x³/(eˣ − 1) dx. Explain every step for a university student and create an animated video with narration.”

Make your own version

Make the next one in this series

• Derive the general formula for ∫₀^∞ x^(s-1)/(e^x - 1) dx using Gamma and zeta functions
• Show how this integral leads to the Stefan-Boltzmann law in blackbody radiation
• Visualize the geometric series expansion of 1/(e^x - 1) and its convergence

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