How To Calculate The Area Of A Circle Inside A Triangle Where The Length Of Three Sides Of The Triangle Are Given?

As with any circle, the area is given by
area = Pi*r²

The radius of an inscribed circle in a triangle with side lengths a, b, and c is
r = √((s-a)(s-b)(s-c)/s)
where
s = (a+b+c)/2.

This means the area can be calculated by
area = Pi*(s-a)(s-b)(s-c)/s