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What is the formula for the area of a region bounded by a single polar curve?

A=12abr2dθA = \frac{1}{2} \int_a^b r^2 d\theta

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What is the formula for the area of a region bounded by a single polar curve?

A=12abr2dθA = \frac{1}{2} \int_a^b r^2 d\theta

What is the formula for the area of a region bounded by two polar curves?

A=12ab(r22r12)dθA = \frac{1}{2} \int_a^b (r_2^2 - r_1^2) d\theta, where r2r_2 is the outer radius and r1r_1 is the inner radius.

How do you find the area between two polar curves?

A=12αβ[f(θ)2g(θ)2]dθA = \frac{1}{2} \int_{\alpha}^{\beta} [f(\theta)^2 - g(\theta)^2] d\theta, where f(θ)f(\theta) is the outer curve and g(θ)g(\theta) is the inner curve.

What is a polar curve?

A curve defined using polar coordinates (r,θ)(r, \theta), where rr is the distance from the origin and θ\theta is the angle from the positive x-axis.

Define polar coordinates.

A two-dimensional coordinate system where each point is determined by a distance rr from a reference point (the pole) and an angle θ\theta from a reference direction (the polar axis).

What does rr represent in polar coordinates?

rr represents the radial distance from the origin to the point in the polar coordinate system.

What does θ\theta represent in polar coordinates?

θ\theta represents the angle measured counterclockwise from the positive x-axis to the line segment connecting the origin to the point.

How do you find the intersection points of two polar curves?

Set the two polar equations equal to each other, r1(θ)=r2(θ)r_1(\theta) = r_2(\theta), and solve for θ\theta. These θ\theta values are the angles at the intersection points.

Outline the steps to find the area between r=3r = 3 and r=32sin(2θ)r = 3 - 2\sin(2\theta) in the second quadrant.

  1. Identify r1=3r_1 = 3 and r2=32sin(2θ)r_2 = 3 - 2\sin(2\theta). 2. Determine bounds: π2\frac{\pi}{2} to π\pi. 3. Set up the integral: A=12π2π[(32sin(2θ))232]dθA = \frac{1}{2} \int_{\frac{\pi}{2}}^{\pi} [(3 - 2\sin(2\theta))^2 - 3^2] d\theta. 4. Evaluate the integral.

How do you determine which polar function is the 'inner' function?

Imagine yourself at the origin. The function you see first is the inner function.