volumes help (1 Viewer)

[Gujju]

find the volume when the triangle bounded by the lines y=x/2 +2 and y=x, is revolved around the x-axis. You must use the cylindrical shell method..I can easily do it with discs but not shell?? thanks!

 

[karnbmx]

You'll have to do it in two parts:

The first part: you consider the shells made between y = 0 and y = 2. They will involve ONLY the line y = x
The second part: you consider the shells made between y = 2 and y = 4/3. They will involve both y = x and y = x/2 + 2.

Then you add the two parts together to get the answer.

 

[Gujju]

You'll have to do it in two parts:

The first part: you consider the shells made between y = 0 and y = 2. They will involve ONLY the line y = x
The second part: you consider the shells made between y = 2 and y = 4/3. They will involve both y = x and y = x/2 + 2.

Then you add the two parts together to get the answer.

Isnt there a shortened method where you can combine them and work as if it is one thing??? Thats really similar to 2 unit method

 

[Fus Ro Dah]

find the volume when the triangle bounded by the lines y=x/2 +2 and y=x, is revolved around the x-axis. You must use the cylindrical shell method..I can easily do it with discs but not shell?? thanks!

There is no triangle bounded by those two lines, unless you mean the area bounded by those two lines and the x or y axis.