







A region described by inequalities in cylindrical coordinates 
20150221 

Rahul pose la question : I am not able to visualize a solid given by inequalities as under (in cylindrical coordinate system)
0=
I know that (can visualize) first 2 inequalities say it is a cylinder of infinite length.
It seems that third inequality poses the restriction to the height as well as it makes us to remove a cone.
But I just can not understand it clearly.
Thanks in advance!
Regards,
Rahul Penny Nom lui répond. 





Cutting a pipe at an arbitrary angle 
20080920 

John pose la question : from the original question Al asked about cutting a 200 diameter pipe in 45 degrees. can someone explain the math steps required to creating the graph. I am trying to do the same thing only using a 150 degree cut. Harley Weston lui répond. 

