1. ## Question about Washer's Method

When it says to rotate about the y-axis, does this mean to solve the integral by dx?

And when it says rotate about the x-axis, does this mean to solve the integral by dy?

Thanks.

2. Originally Posted by elpermic
When it says to rotate about the y-axis, does this mean to solve the integral by dx?

And when it says rotate about the x-axis, does this mean to solve the integral by dy?

Thanks.

other way around

3. This also applies with problems such as rotate around the line x=1 and y=1 right?

4. Originally Posted by elpermic
This also applies with problems such as rotate around the line x=1 and y=1 right?

yes

5. Originally Posted by elpermic
This also applies with problems such as rotate around the line x=1 and y=1 right?

also keep in mind if you are using the cylindrical sheels method you are drawing the line parallel to the axis of rotatio so in this case and this case only is what you said first correct

everything else is the opposite, including all washer problems