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dhokes
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Can someone show me how to do the question below please.

The finite region R is bounded by an arc of the curve with equation r=acos3θ and the half-lines with equations θ=-π/6, θ=π/6. Find the area of T, given that a>0.

:confused:

Is it 0.5∫a²cos²3θ dx between the two limits ? If so, what do I do now?

Thanks
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meef cheese
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(Original post by dhokes)
Can someone show me how to do the question below please.

The finite region R is bounded by an arc of the curve with equation r=acos3θ and the half-lines with equations θ=-π/6, θ=π/6. Find the area of T, given that a>0.

:confused:

Is it 0.5∫a²cos²3θ dx between the two limits ? If so, what do I do now?

Thanks
Yes. a² is a constant so can be taken outside the integral. I think the integral is the same as integrating between θ=0 and θ=π/6 and multiplying by 2. Then write cos²3θ in terms of cos6θ.
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meef cheese
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I get pi a2/12
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