hi Agnishom

How did you get that? It's not what I'm getting.

Here's my method.

SINE RULE is:

So I put

and re-arranged to get

Different values of k will make different sized circles but all the resulting triangles will be similar => same three angles.

So it is ok to take a = √6, b = 2√2, c = 3√3

Use the cosine rule to get cosA and hence sinA.

I made it

Bob