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5. The Area of a Plane Region. (15 points) a. Find the left Riemann sum for the region bounded by the graph of f (x) = xz + 2x + 3 and the x-axis between x = 0 and x = 2. (Limit Definition) b. Use Fundamental Theorem of Calculus to solve part a. n n n n(n + 1) n(n + 1)(2n + 1) M c = nc M i = 12 = 2 6 i=1 i=1 i=1