uploads/710612/images_1.pdfHi there, how can i connect this line to any point on the circle? this is what it looks like when i zoom in.  hope you can help. 

If you use OSNAP, your geometry should be precise - despite it may be displayed disconnected in extreme zoom levels. Make sure your geometry is not too far from the world origin (0,0,0).

If the line is not connected to a quadrant or tangent to the circle then to connect it to any point on the circle try drawing a temporary line that intersects the circle then use the INTERSECTION osnap to make the connection.

If you used some Osnap mode to put it on the Circle, or Trim or Extend, and if this is Zoomed significantly in since then, it's just a matter of display resolution.  REGEN and it will probably meet visually [it really does meet geometrically already].  It's a function of the way curves are segmented in display only.  To at least lessen the effect, go into VIEWRES and give it a higher Circle Zoom Percentage.