Select the third function, y = 2 cos(x), and set the interval to [−4.02, 4.02].(a) With 10 rectangles using left endpoints, how many rectangles are contributing negative area values to the estimated net area? How many are positive?
Question
Select the third function, y = 2 cos(x), and set the interval to [−4.02, 4.02].(a) With 10 rectangles using left endpoints, how many rectangles are contributing negative area values to the estimated net area? How many are positive?
Solution
To answer this question, we first need to understand the behavior of the function y = 2cos(x) over the interval [-4.02, 4.02].
The cosine function oscillates between -1 and 1, and multiplying it by 2 makes it oscillate between -2 and 2. The period of the function is 2π, which means it completes a full cycle every 2π units.
Now, let's divide the interval [-4.02, 4.02] into 10 equal subintervals. Each subinterval will have a width of (4.02 - (-4.02))/10 = 0.804.
The left endpoints of these subintervals will be -4.02, -3.216, -2.412, -1.608, -0.804, 0, 0.804, 1.608, 2.412, and 3.216.
We can plug these values into the function y = 2cos(x) to determine whether the rectangle formed at each subinterval will contribute a positive or negative area.
The cosine function is positive in the first and fourth quadrants (0 to π/2 and 3π/2 to 2π), and negative in the second and third quadrants (π/2 to π and π to 3π/2).
Given that the period of the function is 2π, we can determine that the function will be positive at the left endpoints -4.02, -3.216, 0.804, and 1.608, and negative at the left endpoints -2.412, -1.608, -0.804, 0, 2.412, and 3.216.
Therefore, 4 rectangles will contribute positive area values, and 6 rectangles will contribute negative area values to the estimated net area.
Similar Questions
Select the fourth function, y = 1x2 + 1, and set the interval to [−3, 2].(a) Find the approximate net area for 5 subintervals using left-endpoint rectangles. Find the approximate net area for 5 subintervals using right-endpoint rectangles.
Use left and right endpoints and the given number of rectangles to find two approximations of the area of the region between the graph of the function and the x-axis over the given interval.f(x) = 2x + 9, [0, 2], 4 rectangles
Select the fourth function, y = 1x2 + 1, and set the interval to [−3, 2].(a) Find the approximate net area for 5 subintervals using left-endpoint rectangles.Find the approximate net area for 5 subintervals using right-endpoint rectangles.Find the approximate net area for 5 subintervals using trapezoids.(b) Compute the average of the two rectangle approximations from part (a) and compare this to the trapezoidal estimate. What do you notice?The average of the left and right endpoint approximations is equal to twice the trapezoid approximation.The average of the left and right endpoint approximations is equal to a fourth of the trapezoid approximation. The average of the left and right endpoint approximations is equal to four times the trapezoid approximation.The average of the left and right endpoint approximations is equal to the trapezoid approximation.The average of the left and right endpoint approximations is equal to half the trapezoid approximation.(c) For 10 subintervals, which is more accurate, using trapezoids or rectangles with midpoints?Using trapezoids is more accurate.Using rectangles with midpoints is more accurate. The methods are equally accurate.How do the errors compare?The error using trapezoids is about half the midpoint approximation error.The error using trapezoids is about twice the midpoint approximation error. The error using trapezoids is equal to the midpoint approximation error.The error using trapezoids is about a fourth of the midpoint approximation error.The error using trapezoids is about four times the midpoint approximation error.(d) Click the Simpson button and use Simpson's Rule to approximate the net area with 10 subintervals. Is this more accurate than the Trapezoidal Rule's estimate?YesNo (e) Which is more accurate, Simpson's Rule with 10 subintervals or the Trapezoidal Rule with 50 subintervals?Simpson's Rule with 10 subintervalsTrapezoidal Rule with 50 subintervals By how much do these estimates differ? (Round your answer to five decimal places.)(f) Of the available choices, how many subintervals are needed for the midpoint approximation to be more accurate than Simpson's Rule with 10 subintervals?The midpoint approximation with 15 subintervals is more accurate than Simpson's Rule with 10 subintervals.The midpoint approximation with 26 subintervals is more accurate than Simpson's Rule with 10 subintervals. The midpoint approximation with 38 subintervals is more accurate than Simpson's Rule with 10 subintervals.The midpoint approximation with 50 subintervals is more accurate than Simpson's Rule with 10 subintervals.Simpson's Rule with 10 subintervals is still more accurate than the midpoint approximation with 50 subintervals.
The area under the curve y=|cosx−sinx|, 0≤x≤π2, and above x-axis is :
The region bounded by the x-axis and the part of the graph of y = cos x between x = −π/2 and x = π/2 is separated into two regions by the line x = k. If the area of the region for -π/2 ≤ x ≤ k is three times the area of the region for k ≤ x , then k =
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.