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Ch. 8 - Techniques of Integration
Hass - Thomas' Calculus 15th Edition
Hass15th EditionThomas' CalculusISBN: 9780137616077Non è quello che usi tu?Cambia libro di testo
Capitolo 8, Problema 8.2.59

Finding volume: Find the volume of the solid generated by revolving the region in the first quadrant bounded by the coordinate axes, the curve y = e^x, and the line x = ln(2) about the line x = ln(2).

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Identify the region to be revolved: it is bounded by the coordinate axes (x=0 and y=0), the curve \(y = e^{x}\), and the vertical line \(x = \ln(2)\), all in the first quadrant.
Since the solid is generated by revolving the region about the vertical line \(x = \ln(2)\), consider using the method of cylindrical shells, which is well-suited for rotation around vertical lines.
Set up the volume integral using the shell method. For a typical shell at position \(x\) (where \(0 \leq x \leq \ln(2)\)), the radius of the shell is the horizontal distance from \(x\) to the axis of rotation: \(r = \ln(2) - x\).
The height of the shell is given by the function value at \(x\), which is \(h = e^{x}\). The thickness of the shell is \(dx\).
Write the volume integral as \(V = \int_{0}^{\ln(2)} 2\pi \times (\text{radius}) \times (\text{height}) \, dx = \int_{0}^{\ln(2)} 2\pi (\ln(2) - x) e^{x} \, dx\). This integral can then be evaluated to find the volume.

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Volume of Solids of Revolution

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