Volume Ellipse: Find x,a,b Rotation X-Axis

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To find the volume of an ellipse defined by the equation x^2/a^2 + y^2/b^2 = 1 after rotation over the x-axis, the formula V = πab^2 is used, where a represents the semi-major axis and b the semi-minor axis. The value of x when the ellipse is rotated can be determined by setting y = 0, resulting in x = a. Substituting this into the volume formula confirms that V = πa^2b^2 is the correct expression for the volume. This method effectively calculates the volume generated by the solid figure formed by the rotation. Understanding these steps is crucial for accurately determining the volume of the ellipse.
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Find the volume of an ellipse \frac{x^2}{a^2} + \frac{y^2}{b^2} = 1 after being rotated over the x-axis.
 
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Area generated by the solid fig will be given by

\int_{-a}^{a} \pi y^2 dx
 


To find the volume of an ellipse after being rotated over the x-axis, we can use the formula V = πab^2, where a and b are the semi-major and semi-minor axes of the ellipse. In the given equation, a is the semi-major axis and b is the semi-minor axis.

First, we need to find the value of x when the ellipse is rotated over the x-axis. This can be done by setting y = 0 in the given equation, which gives us x = a.

Now, we can substitute the value of x in the formula V = πab^2 to get V = πa^2b^2. This is the volume of the ellipse after being rotated over the x-axis.

In summary, to find the volume of an ellipse \frac{x^2}{a^2} + \frac{y^2}{b^2} = 1 after being rotated over the x-axis, we use the formula V = πab^2, where a is the semi-major axis and b is the semi-minor axis. We also need to find the value of x when the ellipse is rotated, which can be done by setting y = 0 in the given equation.
 
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