Lets compare the top view of both the Aircraft now and I will tell you the Actual Reality of the so called copy claim.
(Top view comparison of both the fighter Aircrafts)
( Mirage 2000)
( LCA TEJAS)
Now Front View of Both The Aircrafts—
( Tejas )
(MIRAGE 2000)—
If you look from the front, you will notice that there is a significant amount of difference in both the Planes.
In tejas , the inlets are located just below the wings and in mirage 2000 they are located above the wings, here is another difference.
Side view of both the Aircrafts
( Mirage 2000)
( Tejas )
Now compare the view from the underside of the both Aircrafts , they will look similar but they are not completely the same though right?
( MIRAGE 2000)
( Tejas )
Now compare both the Aircrafts from this angle:
( Tejas )
( Mirage 2000)
Here too you will notice some noticable changes in their respective design. Both Aircrafts have some design similarities in Them ( no doubt about it ) but calling Tejas an outright copy of the Mirage 2000 is absurd in my opinion
So you see they look similar in shape because they both are Delta-wing configuration Fighter Aircrafts in a sense .
So no — Tejas is not an out Right copy of Mirage 2000 fighter aircraft,it is just that both of the Aircraft are Delta wing design so hence they look similar.