Surface area of a sphere, and area at work
Mathematics · Grade 9 · about 40 minutes
A sphere has surface area 4 pi r squared; close the sub-strand by choosing the right method for real surfaces.
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- 10 sections of explanation, worked examples and diagrams
- 1 practice task with hints and worked answers
- A quiz that marks itself as you go
- Your progress kept across every subject you take
Other lessons in this sub-strand
- Area of a pentagon and a hexagon
- Nets: opening a solid out flat
- Surface area of prisms
- Surface area of pyramids
- Area of a sector
- Area of a segment
- Surface area of a cone
- Surface area of a sphere, and area at work