Posted by Mooch on .
The region R is bounded by the xaxis, x = 1, x = 3, and y = 1/x^3.
Here is what I have so far:
Radius = 1/(x^3)
Area of Cross Section = pi(1/(x^3))^2
Simplified: pi(1/(x^6))
Volume = (definite integral from 1 to 3) pi(1/(x^6)) dx
= pi( 1 / 5(3)^5)  pi(1 / 5(1)^5)
= pi (1 / 1215)  pi (1 / 5)
= pi(242 / 1215) = 0.625732858
Is this right?
Sincerely,
Mooch

Calculus Check 
Steve,
just right. good job.

Calculus Check 
Mooch,
Thank you. From now on, I will include my work for reference. As you can see, I do know (to a degree) what I am doing. However, my practice instructions aren't always very clear on how to carry out these problems so I look for a second opinion to back me up. Again, thank you.