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Do Now: p.381: #8. Integrate the two parts separately:. Shaded Area =. Integrating with Respect to y. Section 7.2b. Integrating with Respect to y. Sometimes the boundaries of a region are more easily described by functions of y than by functions of x . In such
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Do Now: p.381: #8 Integrate the two parts separately: Shaded Area =
Integrating with Respect to y Section 7.2b
Integrating with Respect to y Sometimes the boundaries of a region are more easily described by functions of y than by functions of x. In such cases, we can use horizontal rectangles: d d c c
Returning to an example from last class… Find the area of the region R in the first quadrant that is bounded above by and below by the x-axis and the line . Solve our previous equations for x: 2 (4,2) 1 2 4
Returning to an example from last class… And a third way to handle this example: Using geometry formulas. (4,2) 2 Integrate the square root function from 0 to 4, then subtract the area of the triangle on the right: 1 2 2 2 4
Quality Practice Problems Try #4 from p.380:
Quality Practice Problems Find the area of the region enclosed by the given functions. How about the graph? To find the y-coordinates of the Intersection points, solve: (4,2) (1,–1)
Quality Practice Problems Find the area of the region enclosed by the given functions. Use your calculator to graph in [–3, 3] by [–3, 3]. We could integrate with respect to x, but that would require splitting the region at x = a. (c,d) Instead, let’s integrate from y = b to y = d, handling the entire region at once… (a,b)
Quality Practice Problems Find the area of the region enclosed by the given functions. Use your calculator to graph in [–3, 3] by [–3, 3]. Calculate b and d, storing the values in your calculator: (c,d) (a,b) Evaluate the area numerically:
Do Now: p.381: #8 Returning to the “Do Now,” let’s use our new technique!!! Shaded Area =
Quality Practice Problems Find the area of the region between the curve and the line by integrating with respect to (a) x, (b) y. Integrate with respect to x: Graph the region: (–2,–1) (2,–1)
Quality Practice Problems Find the area of the region between the curve and the line by integrating with respect to (a) x, (b) y. Integrate with respect to y: Graph the region: (–2,–1) (2,–1)
Find the area of the region in the first quadrant bounded on the left by the y-axis, below by the line , above left by the curve , and above right by the curve Graph the region: Integrate in two parts: x = 1 x = 4
Find the area of the region in the first quadrant bounded on the left by the y-axis, below by the line , above left by the curve , and above right by the curve Graph the region: x = 1 x = 4