Consider the polar curves and

MATHEMATICS · Multi-part · AP · Calculus BC · Parametric, Polar, and Vector-Valued Functions · Parametric, Polar, and Vector-Valued Functions

Problem

Consider the polar curves C1:r=2+cos⁡θC_1: r = 2 + \cos \theta and C2:r=3sin⁡θC_2: r = 3 \sin \theta. The curves bound a finite region that lies entirely in the first quadrant. (a) Determine all values of θ\theta in [0,π2][0,\tfrac{\pi}{2}] where C1C_1 and C2C_2 intersect. (b) For each sub-interval you identify in part (a), indicate which curve forms the outer boundary of the region and which curve forms the inner boundary. Justify your conclusion without evaluating any integrals. (c) Write, but do not evaluate, the integral expression that represents the exact area of the region bounded by C1C_1 and C2C_2 in the first quadrant. (d) Explain how the sign of the integrand in part (c) would change if the inner and outer curves were mistakenly reversed, and describe the geometric consequence of this error.

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