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Do you still remember the formulae for calculating the area or volume of circle in IGCSE/GCSE Maths?
Circles
- Circle Area ⟶ 𝛑𝑟²
- Circumference ⟶ 𝛑𝑫
- Semi - Circle Area ⟶ 𝛑𝑟² ÷ 2
- Semi - Circle Perimeter ⟶ (𝛑𝑫 ÷ 2) + 𝑫
- Area of a sector ⟶ 𝚹/360 x 𝛑𝑟²
- Length of an arc ⟶ 𝚹/360 x 𝛑𝑫
- Perimeter of Sector ⟶ 𝚹/360 x 𝛑𝑫 + 𝑫
Area
- Triangle Area ⟶ 𝑏×ℎ÷2
- Trapezium Area ⟶ ½(𝑎+𝑏) × ℎ
- Parallelogram Area ⟶ 𝑏×ℎ
- Cuboid Volume ⟶ 𝑙 × w × ℎ
- Prism volume ⟶ area of cross section × ℎ/length
- Cylinder volume ⟶ 𝛑𝑟²ℎ = (area of cross section x height)
- Cylinder Surface area ⟶ 𝛑𝑫 x ℎ + 2(𝛑𝑟²) = Curved SA + area of 2 bases
- Curved SA of cylinder ⟶ 𝛑𝑫 x ℎ = circumference x height
- Pyramid volume ⟶ ⅓𝑏×ℎ = ⅓(area of base x height)
- Cone Volume ⟶ ⅓𝛑𝑟²ℎ = ⅓(area of base x height)
- Cone Surface area ⟶ 𝛑𝑟𝑙 + (𝛑𝑟²/area of base) where 𝑙 = √r² + h²
- Perimeter ⟶ Circumference proportion + left over sides
- Sphere volume ⟶ 4/3𝛑𝑟³
- Sphere SA ⟶ 4𝛑𝑟²
- Hemisphere ⟶ (4/3𝛑𝑟³) ÷2
- Hemisphere SA ⟶ 2𝛑𝑟² + base area
- Length x:y
- Area x²:y²
- Volume x³:y³
- Smaller surface/area = bigger pressure exerted as the force cannot spread.
That's the end of the topic!
Drafted by Bonnie (Mathematics)