[kristo]

I'm supposed to find the blue colored surface area in both tasks.

1 The radii of the circles are 3 cm and 1 cm, I have no idea what to do here lol..
http://img338.imageshack.us/img338/1630/graph1zd7.png

2 Find a formula for the surface area of the rosette in the equal-sided triangle.
This is the figure in my textbook:
http://img87.imageshack.us/img87/2590/graph2dj9.png

This is what I've done:
Since all angles in an equal-sided triangle are 60 degrees and the sides of the triangle is acting like a tangent line for the circle( Circle Tangent Line -- from Wolfram MathWorld), the angle inside the circle is 180-60=120 degrees.
Well, here's the picture of what I did, the area of the rosette in the triangle is the area of 3 segments minus the area of the triangle.
http://img339.imageshack.us/img339/4650/circlerd9.png

The solution I got is , but the book says it's