What does the radius function r(x) or r(y) represent in the shell method?
Distance from axis of revolution
What is the shell method used for in calculus?
Finding volume of a solid
Steps for finding volume using the shell method
1️⃣ Visualize the solid as cylindrical shells
2️⃣ Set up an integral with the differential element
3️⃣ Integrate to find the total volume
The axis of revolution determines the orientation of the **cylindricalshells
Match the visualization method with its differential element:
Shell Method ↔️ Volume of a shell
Disc Method ↔️ Volume of a disc
The shell method is particularly useful for complex solids where the disc method is difficult to apply.
True
The axis of revolution defines the integration variable based on the shell orientation
In the shell method, the solid is visualized as a series of **cylindricalshells
For what type of solids is the shell method particularly useful?
Irregularly-shaped solids
The axis of revolution must be identified before using the shell method.
True
If the axis of revolution is the y-axis, what is r(x) for a point (x,y) on the region?
r(x)=x
The shell method is often preferred over the disc method for complex solids.
True
Steps to calculate the volume of a solid of revolution using the shell method
1️⃣ Visualize cylindrical shells around the axis of rotation
2️⃣ Create an integral representing the volume of an individual shell
3️⃣ Integrate to find the total volume
The axis of revolution determines the orientation of the cylindrical shells
The radius function represents the distance from the axis of revolution to a cylindrical shell
What is the radius function if the axis of revolution is the y-axis and a point on the region has coordinates (x,y)?
r(x)=x
The shell method formula for horizontal shells is V=∫cd2πr(y)h(y)dy, where r(y) and h(y) depend on the geometry of the solid
Steps to set up the volume integral using the shell method
1️⃣ Identify the axis of revolution
2️⃣ Determine the radius function
3️⃣ Determine the height function
4️⃣ Apply the appropriate formula for vertical or horizontal shells
The shell method calculates the volume of a solid of revolution by visualizing it as stacked cylindrical shells
The height function in the shell method is determined by the difference between the upper and lower boundaries of the region being revolved.
True
For vertical shells, the height function is h(x)= f_{\text{upper}}(x) - f_{\text{\lower}}(x), while for horizontal shells, it is h(y)= g_{\text{\right}}(y) - g_{\text{\left}}(y) height
What is the shell method formula for vertical shells?