Unless specified, all approximating rectangles are assumed to have the same width. X (a) Estimate the area under the graph of f, the x-axis, and the lines x = 1 and x = 2 using four approximating rectangles and right endpoints. (Round your answer to four decimal places.) Let f(x) = Sketch the graph and the rectangles. y 3 2 O 3 y 3 2- x 2 1 2 1 2