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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 8.4.59b

Consider the region bounded by the graphs of y = sin⁻¹(x), y = 0, and x = 1/2.
b. Find the centroid of the region.

Guida verificata passo dopo passo
1
Identify the region bounded by the curves: the inverse sine function \(y = \sin^{-1}(x)\), the line \(y = 0\), and the vertical line \(x = \frac{1}{2}\). This region lies between \(x = 0\) and \(x = \frac{1}{2}\) because \(\sin^{-1}(0) = 0\) and the lower boundary is \(y=0\).
Set up the formulas for the coordinates of the centroid \((\bar{x}, \bar{y})\) of a planar region bounded by curves. The centroid coordinates are given by: \(\displaystyle \bar{x} = \frac{1}{A} \int_a^b x \cdot f(x) \, dx\) and \(\displaystyle \bar{y} = \frac{1}{2A} \int_a^b [f(x)]^2 \, dx\), where \(f(x) = \sin^{-1}(x)\), \(a=0\), \(b=\frac{1}{2}\), and \(A\) is the area of the region.
Calculate the area \(A\) of the region using the integral: \(\displaystyle A = \int_0^{\frac{1}{2}} \sin^{-1}(x) \, dx\). This integral represents the area under the curve \(y = \sin^{-1}(x)\) from \(x=0\) to \(x=\frac{1}{2}\) above the \(x\)-axis.
Compute the integrals needed for the centroid coordinates: - For \(\bar{x}\), evaluate \(\int_0^{\frac{1}{2}} x \sin^{-1}(x) \, dx\). - For \(\bar{y}\), evaluate \(\int_0^{\frac{1}{2}} (\sin^{-1}(x))^2 \, dx\). These integrals may require integration by parts or substitution techniques.
Finally, substitute the values of the integrals and the area \(A\) into the centroid formulas: \(\displaystyle \bar{x} = \frac{1}{A} \int_0^{\frac{1}{2}} x \sin^{-1}(x) \, dx\) and \(\displaystyle \bar{y} = \frac{1}{2A} \int_0^{\frac{1}{2}} (\sin^{-1}(x))^2 \, dx\). This will give the coordinates of the centroid of the region.

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