Find the area of the region.interior of r2 = 16 cos(2𝜃)
Question
Find the area of the region.interior of r2 = 16 cos(2𝜃)
Solution
To find the area of the region inside the polar curve r^2 = 16cos(2θ), we can use the formula for the area A of a polar curve, given by:
A = 1/2 ∫[a,b] (r(θ))^2 dθ
Here, r(θ) = sqrt(16cos(2θ)) = 4|cos(θ)|. The absolute value is because the radius cannot be negative.
The curve r = 4cos(θ) is a circle with radius 2 centered at (2, 0) in the polar coordinate system. It completes one loop when θ changes from 0 to π, and another loop when θ changes from π to 2π.
So, to find the area of the region inside the curve, we need to integrate from 0 to π, and then double the result:
A = 2 * 1/2 ∫[0,π] (4cos(θ))^2 dθ = 2 ∫[0,π] 16cos^2(θ) dθ
We can use the power-reduction identity cos^2(θ) = 1/2(1 + cos(2θ)) to simplify the integrand:
A = 2 ∫[0,π] 16/2(1 + cos(2θ)) dθ = 16 ∫[0,π] (1 + cos(2θ)) dθ
This integral can be easily computed:
A = 16 [θ + 1/2 sin(2θ)] from 0 to π = 16 [π + 1/2 sin(2π) - 0 - 1/2 sin(0)] = 16π
So, the area of the region inside the curve r^2 = 16cos(2θ) is 16π square units.
Similar Questions
Sketch the region enclosed by the given curves.y = 4 cos(𝜋x), y = 8x2 − 2 Find its area.
Use a graphing utility to graph the polar equations. Find the area of the given region analytically.common interior of r = 8 sin(2𝜃) and r = 4
Find the volume of the region below the graph of f (x, y) = 16 − x2 − y2 and above thexy-plane in the first octant. Hint: convert to polar coordinates
Find the area of the region.interior of r = 5 + 3 sin(𝜃) (below the polar axis
Evaluate the integral of f (x, y) = x over the region given by 4 ≤ x2 + y2 ≤ 16. Hint: convertto polar coordinates.Page 2 of 2
Upgrade your grade with Knowee
Get personalized homework help. Review tough concepts in more detail, or go deeper into your topic by exploring other relevant questions.