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Find the volume of the solid formed by rotating the region enclosed below-axis.
Volume =______.

1 Answer

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1. The volume of the solid formed by rotating the region enclosed by
\(y=e^(2x) + 3\), \(y=0\), \(x=0\), \(x=0.9\) about the x-axis is approximately
\(51.67 \pi\).

2. The volume of the solid obtained by rotating the region bounded by
\(y=(1)/(√(x+3))\), \(x=3\), \(x=9\), and \(y=0\) about the x-axis is
\(\pi \ln 2\).

3. For the solid formed by rotating the region bounded by
\(y=e^(3x)+3\) and
\(x=0.5\) about the x-axis, the volume depends on the upper limit of integration
\(b\).

Question 1:

To find the volume of the solid formed by rotating the region enclosed by
\(y=e^(2x) + 3\), \(y=0\), \(x=0\), \(x=0.9\) about the x-axis, we can use the disk method. The volume
\(V\) is given by:


\[V = \pi \int_(0)^(0.9) (e^(2x) + 3)^2 \,dx\]

Now, integrate with respect to \(x\):


\[V = \pi \int_(0)^(0.9) (e^(4x) + 6e^(2x) + 9) \,dx\]


\[V = \pi \left[(1)/(4)e^(4x) + 3e^(2x) + 9x\right]_(0)^(0.9)\]


\[V = \pi \left[(1)/(4)e^(3.6) + 3e^(1.8) + 9(0.9)\right]\]


\[V \approx 51.67 \pi\]

Therefore, the volume of the solid formed by rotating the region about the x-axis is approximately
\(51.67 \pi\).

Question 2:

To find the volume of the solid obtained by rotating the region bounded by
\(y=(1)/(√(x+3))\), \(x=3\), \(x=9\), and
\(y=0\) about the x-axis, we again use the disk method. The volume
\(V\) is given by:


\[V = \pi \int_(3)^(9) \left((1)/(√(x+3))\right)^2 \,dx\]

Now, integrate with respect to
\(x\):


\[V = \pi \int_(3)^(9) (1)/(x+3) \,dx\]


\[V = \pi \ln|x+3| \Big|_(3)^(9)\]


\[V = \pi (\ln 12 - \ln 6)\]


\[V = \pi \ln 2\]

The volume of the solid formed by rotating the region about the x-axis is
\(\pi \ln 2\).

Question 3:

The solid formed by rotating the region bounded by
\(y=e^(3x)+3\) and \(x=0.5\) about the x-axis can be calculated using the disk method:


\[V = \pi \int_(0.5)^(b) (e^(3x) + 3)^2 \,dx\]

After integrating and evaluating, the volume
\(V\) can be expressed in terms of
\(b\).

The volume of the solid formed by rotating the region about the x-axis depends on the upper limit of integration
\(b\).

The question probable maybe:

1. Find the volume of the solid formed by rotating the region enclosed by y=e^2x +3, y=0, x=0, x=0.9 about the x-axis. Volume:____

2. Find the volume of the solid obtained by rotating the region bounded by y=1/√ (x+3), x=3, x=9, and y=0, about the x-axis. Volume:____

3. A solid is formed by rotating the region in the first quadrant of the xy-plane bounded by the graphs of y=e^3x+3 and x=0.5 about the x-axis. Volume:____

User Johnmcase
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