Area of a circle

Arcs

Sectors

back to top

Segments

back to top

Triangles

A triangle is incribed in a rectangle (height h width b). The perpendicular divides the shape.

It can be seen that each rectangle formed is composed of two triangles of equal area.

Hence the area of the original triangle is half that of the rectangle.

The expression containing the sine is really the same as above.

Parallelograms

Trapeziums

back to top