NO TRIM allows you to create an arc fillet but not trim 
the tangent entities at their intersections with the 
fillet.

Enter a value for the radius of the arc fillet and press
<Enter>, or accept the default value by pressing <Enter>.

Select the first entity near the tangency point. To cancel
the first selection, choose the BACK-UP option and select 
a different entity.

Select the second entity near the tangency point. If the
specified radius is greater than half of the maximum
distance between the selected entities, an error message 
is displayed. If this occurs, press <Enter>, choose the
BACK-UP option, enter a different radius value, and 
reselect the entities.

In 2-D construction mode, the selected entities are
projected to the current construction view, at the current
depth. The arc fillet is created in the current 
construction view, at the depth that is active when the 
second entity is selected. 

In 3-D construction mode, the arc fillet is created in the
plane defined by the selected entities.
