Surface Area Qs. (1 Viewer)

[x3.eddayyeeee]

Although this may seem strange ,
but can someone explain the proof of getting the surface area of a cone.
ie. πrs + πr<SUP>2</SUP>, where r is the radius of the cone and s is the slant height

EDIT: dont worry. worked it out.

 

[x.Exhaust.x]

Why do you need to know the proof?

 

[x3.eddayyeeee]

its just a habit of mine.
so incase i forget the formula, i can use the proof to help me get the formula again.

 

[lyounamu]

Nice, man. That's the way!

That's the approach that will get you beyond Band 6 in maths.