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Active Calculus 2nd Ed

Activity 5.2.2.
Suppose that \(f\) is the function given in Figure 5.2.2 and that \(f\) is a piecewise function whose parts are either portions of lines or portions of circles, as pictured.
Figure 5.2.2. At left, the graph of \(y = f(x)\text{.}\) At right, axes for sketching \(y = A(x)\text{.}\)
In addition, let \(A\) be the function defined by the rule \(A(x) = \int_2^x f(t) \, dt\text{.}\)
(a)
What does the Second FTC tell us about the relationship between \(A\) and \(f\text{?}\)
(b)
Compute \(A(1)\) and \(A(3)\) exactly.
(c)
Sketch a precise graph of \(y = A(x)\) on the axes at right that accurately reflects where \(A\) is increasing and decreasing, where \(A\) is concave up and concave down, and the exact values of \(A\) at \(x = 0, 1, \ldots, 7\text{.}\)
(e)
With as little additional work as possible, sketch precise graphs of the functions \(B(x) = \int_3^x f(t) \, dt\) and \(C(x) = \int_1^x f(t) \, dt\text{.}\) Justify your results with at least one sentence of explanation.