How to make two joined curves smooth/seamless?

Rhino
1

If you have two curves and you join them at their end points, how do you make them seamless at the joint instead of knotted with a sharp bend?

2

Hello - you can explode them and Match for tangency or curvature with Average set, ot RemoveKnot at that location.
To go the other way, InsertKink.

-Pascal