Non-similar triangles...

dbt

How many non-similar trinagles can be constructed whose vertices are vertices of a

1) 21-sided regular polygon?
2) regular n-gon ?

PS - I don't know if this is the r8 forum for this, coz it may not be a JEE problem as such.

4 Answers

I think you can look at isoseles and scalene triangles seperately....

I somehow have the feeling that we have seen this question on the forum before.

1) 435 ?

1) 395?

I don't have the answer.
Post ur methods/thoughts.

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