geometric problem

Could anyone help me to show me how to use the bolean functions for this
purpose:

I try to make a volume out of 2 curves : i.e. 2 circles, non concentric,
and why not in 2 non parallel plans???

thanks in advance 4 your help !!
vanzac

 

Try the SUBTRACT command if you can use solids.

 

Two circular arcs segments can define a surface but not a solid.
Only if they intersect at two points will they define a solid.
this will look like a notch cut out of a cone or cylinder.
Please give more details. I like the problem.