Hey see how we usually get max and min problems, and we usually need to know our surface area and volume formulas, ive only really learnt a cylinders formulas, i hvent come across any i dont think, do i need to know the cone pyramids etc ??
Max and Mins (1 Viewer)
- Thread starter sannous1
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it's just a third of a cylinder
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The pyramids are all the same; V = Ah/3 where A is the area of the base.
The cone is just a special case of this where they have substituted in the area of a circle, giving V = pi r^2 h/3.
Generally they will give you a formula, though do realise that this is year 10 knowledge, and so it can be assumed.
For any cube or rectangular prism it's pretty obvious that you just find the product of the sides.
SA is also obvious for a cube or prism. I doubt they'd ask it for a cone, but it's V = pi * r^2 + pi * r * l, where r is the radius and l is the length along the slant of the cone.
Volume of a sphere is 4pi r^3/3, and surface area is 4pi r^2. Just divide by 2 for a hemisphere.
The cone is just a special case of this where they have substituted in the area of a circle, giving V = pi r^2 h/3.
Generally they will give you a formula, though do realise that this is year 10 knowledge, and so it can be assumed.
For any cube or rectangular prism it's pretty obvious that you just find the product of the sides.
SA is also obvious for a cube or prism. I doubt they'd ask it for a cone, but it's V = pi * r^2 + pi * r * l, where r is the radius and l is the length along the slant of the cone.
Volume of a sphere is 4pi r^3/3, and surface area is 4pi r^2. Just divide by 2 for a hemisphere.