Triangle Circle Pattern
1. The problem involves studying the iterative pattern formed by an equilateral triangle and its circumscribed circle, each inscribed within the other repeatedly.
2. First, define the side length of the initial equilateral triangle as $s_1$ and its circumradius as $R_1 = \frac{s_1}{\sqrt{3}}$.
3. The circle inscribed inside this triangle has radius $R_1$, then a smaller equilateral triangle is inscribed inside that circle.
4. Using the formulas:
- Area of equilateral triangle: $A_t = \frac{\sqrt{3}}{4}s^2$
- Radius of circumcircle: $R = \frac{s}{\sqrt{3}}$
- Area of a circle: $A_c = \pi R^2$
5. Each successive figure is a scaled version of the previous with a constant scale factor $r$, forming a geometric sequence.
6. For similarity ratio between successive shapes, note that the side length of the next triangle inside the circle is related to the radius of that circle, and the circle radius is related to the previous triangle's side length.
7. This gives a consistent ratio $r = \frac{1}{2}$ between successive side lengths and radii, since inscribing an equilateral triangle in the circle reduces the size by this ratio.
8. The area of triangles and circles form geometric sequences with ratios $r^2 = \frac{1}{4}$ because area scales by the square of the linear scale factor.
9. The total area converges as an infinite geometric series for both triangles and circles; sum to infinity formula $S = \frac{a_1}{1-r}$ applies, with first term $a_1$ as the area of the initial shapes and ratio $r = \frac{1}{4}$.
10. Therefore, the total areas and perimeters have finite limits even as the process continues infinitely.
In conclusion:
- The radius of each circle relates to the side length of the triangle by $R = \frac{s}{\sqrt{3}}$.
- Area changes by a factor of $\frac{1}{4}$ each iteration.
- Similarity ratio of successive figures is $\frac{1}{2}$.
- The total area converges to $S = \frac{A}{1 - (\frac{1}{4})}$ where $A$ is the first area.
Hence, yes, these geometric relationships and formulas correctly describe the infinite iterative pattern of triangles and circles.