View of the Surface Area of A Cone

Find the area of the curved surface area of the cone of base radius [i]r[/i] and slanted height [i]l[/i]. (Click https://ggbm.at/206987to see how the curved surface area of the cone equals this sector).
Anthony C.M. Or[br]GeoGebra Institute of Hong Kong
Start here. Open it in a new window so you can answer the questions below
What
What do you notice as you flatten the cone?
What dimensions are present?
What are the two areas you have left in the cone once it is flattened?
Open the link in a new window so you can continue and answer the questions below.
Click the "Dissect the Sector" button.
Does it matter how may slices you have?
Set it to six and then hit the rearrange button. What happenes?
As you laid it out what shapes do you notice?
How does this support the equation?
Close
– juliesgotmail, Anthony OR 柯志明

Information: View of the Surface Area of A Cone