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Sketch the region enclosed by the given curves: y = 3 cos x, y = 8x² - 2?

User Myroslava
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Final answer:

To sketch the region between y = 3 cos x and y = 8x² - 2, plot both curves on the same graph, find their points of intersection, and shade the enclosed region that lies between them.

Step-by-step explanation:

To sketch the region enclosed by the curves y = 3 cos x and y = 8x² - 2, you need to follow these steps:

  1. Determine the interval for x within which the curves might intersect. For trigonometric functions like cosine, considering one or two periods is typically sufficient. For y = 3 cos x, since cosine fluctuates between -1 and 1, y will range from -3 to 3.
  2. Plot the function y = 3 cos x which will be a cosine wave with an amplitude of 3 on a graph.
  3. Plot the function y = 8x² - 2 which is a parabola opening upwards with its vertex at (0,-2).
  4. Identify the points of intersection by setting the two equations equal to each other and solving for x: 3 cos x = 8x² - 2. This may require numerical methods or graphing to approximate since it's not solvable with elementary algebra.
  5. Shade the region on the graph that is enclosed between the two curves, this is the area where the curve y = 8x² - 2 lies above the curve y = 3 cos x.

These intersections will determine the limits of the region you're interested in. The enclosed region can be shaded to ensure clarity.

User Litbear
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7.5k points