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Papers 1 and 2 · Pure7.3 Differentiation

Question 1 · 7 marks

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Spec and skills
  • Paper scope: Pure 1/2
  • Spec P7.3
  • Spec OT3.1
  • Original practice question
A closed cylindrical tin has radius rr cm and volume 250π cm3250\pi\text{ cm}^3.
(a)
Show that the total surface area, S cm2S\text{ cm}^2, is S=2πr2+500πrS = 2\pi r^2 + \dfrac{500\pi}{r}.
2 marks

From the volume, πr2h=250π\pi r^2 h = 250\pi.

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