Due date: Sunday 2/8, 11:59pm

Arc length

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Arc length - tricky integration

Find the arc length of the curve for .

(Hint: the integral can be done using either: (i) -sub then trig sub, or (ii) ‘rationalization’ then partial fractions.)

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Surface areas of revolutions - thin bands

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Surface area: cone

A cone may be described as the surface of revolution of a ray emanating from the origin, revolved around the -axis.

Let for some . Find the surface area of the cone given by revolving the graph of around the -axis over .

Can you also calculate this area using geometry? And verify the two methods give the same formula? (Hint: ‘unroll’ the cone into a sector.)

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Surface area: parabolic reflector

A parabolic reflector is given by rotating the curve around the -axis for .

What is the surface area of this reflector?

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