numbers and algebraic expressions
logic, sets, intervals
function and its properties
limits of sequences and functions
derivative and integral of functions
elements of statistics
Length of a circle arc: l = α/360° * 2πr. Arc of a circle sector: P = α/360° * πr^2. π ≈ 3.14. Circle segment. Area of a circle segment = Area of a circle sector - Area of a triangle.