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26. Consider the function f(x) = V1 - x . (Hint: This is the upper half of a circle of radius 1 positioned at (0, 0).) a. Sketch the graph of f over the interval [- 1, 1]. b. Use the graph in part a to find the approximate area between the x-axis and the graph of f over the interval [- 1, 1] using 8 rectangles. Each rectangle will have a width of Evaluate f(x) at what is known as the right endpoint. That is the following 8 values of X: -3 -1 -1, 0, 4' 2' 4' 4 ' 2 ' 4 , 1, 1, 3, 0. The evaluation of f(x) at each of these values represents the height of the rectangle at the given value of x. Use geometry to find the exact