Write the following function:

```python
def area_of_polygon_inside_circle(circle_radius, number_of_sides):
```

It should calculate the area of a regular polygon of `numberOfSides`, `number-of-sides`, or `number_of_sides` sides inside a circle of radius `circleRadius`, `circle-radius`, or `circle_radius` which passes through all the vertices of the polygon (such circle is called [**circumscribed circle** or **circumcircle**](https://en.wikipedia.org/wiki/Circumscribed_circle)). The answer should be a number rounded to 3 decimal places. 

Input :: Output Examples 

```python
area_of_polygon_inside_circle(3, 3) # returns 11.691

area_of_polygon_inside_circle(5.8, 7) # returns 92.053

area_of_polygon_inside_circle(4, 5) # returns 38.042
```

Difficulty: EASY
Starter code: def area_of_polygon_inside_circle(r, n):
	

Solutions:
from math import sin, pi

def area_of_polygon_inside_circle(r, n):
	return round(0.5 * n * r ** 2 * sin(2 * pi / n), 3)


import math

def area_of_polygon_inside_circle(circle_radius, number_of_sides):
	r = circle_radius
	s = number_of_sides
	a = s * r ** 2 * math.sin(2 * math.pi / s) / 2
	return round(a, 3)


def area_of_polygon_inside_circle(r, n):
	import math
	a = 360 / (2 * n) * 0.017453292519943295
	b = 2 * r * math.sin(a)
	c = r * math.cos(a)
	return round(1 / 2 * b * c * n, 3)


from math import sin, tau

def area_of_polygon_inside_circle(circle_radius, number_of_sides):
	s = number_of_sides / 2 * circle_radius ** 2 * sin(tau / number_of_sides)
	return round(s, 3)


from math import sin, pi

def area_of_polygon_inside_circle(radius, sides):
	return round(sides * radius * radius * sin(pi * (sides - 2) / sides) / 2, 3)