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Multiple Choice
Find the area of the region enclosed by the inner loop of the curve .
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Verified step by step guidance
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Step 1: Understand the problem. The curve is given in polar form as r = 6 + 12 sin(θ). To find the area enclosed by the inner loop, we need to identify the range of θ values where the inner loop occurs. This happens when r becomes zero, so solve 6 + 12 sin(θ) = 0 for θ.
Step 2: Solve 6 + 12 sin(θ) = 0. Rearrange the equation to find sin(θ) = -1/2. Use the unit circle to determine the values of θ where sin(θ) = -1/2. These values will give the bounds for the integral.
Step 3: Set up the area formula for a polar curve. The area enclosed by a polar curve is given by A = (1/2) ∫[θ₁, θ₂] r² dθ, where θ₁ and θ₂ are the bounds of θ determined in Step 2. Substitute r = 6 + 12 sin(θ) into the formula.
Step 4: Expand r² = (6 + 12 sin(θ))². Simplify this expression to prepare for integration. You will get terms involving constants, sin(θ), and sin²(θ). Recall that sin²(θ) can be rewritten using the identity sin²(θ) = (1 - cos(2θ))/2.
Step 5: Integrate the expanded expression for r² over the bounds of θ found in Step 2. Break the integral into manageable parts, compute each term, and sum them up. Multiply the result by 1/2 to find the area of the inner loop.