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Find the area of the region enclosed by one loop of the curve. r=sin(12θ)

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Answer: Area of the region enclosed by one loop of the curve r= sin(12Φ) is π/48.

Step-by-step explanation: Given the curve is r= sin(12Φ).

The range of the Φ is 0 <= Φ <= π/12.

The formula of Area (A) is given as:

A= ∫ 1/2 r^² dΦ

Inserting the limits and the r:

A = \int_0^{\dfrac{\pi}{12}} \space \dfrac{1}{2} (sin(12 \theta))^2 d\theta

A = \dfrac{1}{2} \int_0^{\dfrac{\pi}{12}} \space sin^2(12 \theta) d\theta

Using the formula:

sin^2x = \dfrac{1-cos2x}{2}

A = \dfrac{1}{2} \int_0^{\dfrac{\pi}{12}} \space \dfrac{1-cos(24 \theta)}{2} d\theta

=A = \dfrac{1}{2} \int_0^{\dfrac{\pi}{12}} \space \dfrac{1-cos(24 \theta)}{2} d\theta

= \dfrac{1}{2} \left[ \int_0^{\dfrac{\pi}{12}} \space \dfrac{1}{2} d \theta \space – \space \int_0^{\dfrac{\pi}{12}} \space \left( \dfrac{1-cos(24 \theta)}{2} \right) d\theta \right]

Integrating with respect to dΦ :

A = \dfrac{1}{2} \left[ \left( \dfrac{\theta}{2} \right)_0^{\dfrac{\pi}{12}} \space – \space \left( \dfrac{1-sin(24 \theta)}{2(24)} \right)_0^{\dfrac{\pi}{12}} \right]

= \dfrac{1}{2} \left[ \left( \dfrac{\pi/12}{2} – \dfrac{0}{2} \right) \space – \space \left( \dfrac{1-sin(24 \dfrac{\pi}{12})}{48} \space – \space \dfrac{1-sin(24 (0))}{48} \right) \right]

= \dfrac{1}{2} \left[ \left( \dfrac{\pi}{24} \right) \space – \space \left( \dfrac{\pi}{24} – \dfrac{\pi}{24} \right) \right]

= \dfrac{1}{2} \left[ \left( \dfrac{\pi}{24} \right) \right]

A = \dfrac{\pi}{48}

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User CalMlynarczyk
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