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Let f(x) = 12 - 2x. (a) Sketch the region R under the graph of fon the interval [0, 6]. 12 12 12 12 10 10- 10- 10 8 8 8 6 4 4 4 4 The xy-coordinate plane is given. The is 1 line and a aded region on the graph. 21 2 The line enters the window at y = 11\\ the positive Yraxis, goes down and right, and exits t indow O 15 on the positive *-axis4 . The region is below the line. 5 6 7 AO 2 3 4 5 6 7 1 2 3 4 5 6 7 AO 2 3 4 5 6 7 Find its exact area (in square units) using geometry. square units (b) Use a Riemann sum with five subintervals of equal length (n = 5) to approximate the area (in square units) of R. Choose the representative points to be the right endpoints of the subintervals. square units (c) Repeat part (b) with ten subintervals of equal length (n = 10). square units (d) Compare the approximations obtained in parts (b) and (c) with the exact area found in part (a). Do the approximations improve with larger n? O Yes No