Two functions and are defined on the interval as follows

MATHEMATICS · Multi-part · CBSE · Mathematics · Integrals · Integrals

Problem

Two functions ff and gg are defined on the interval 0≤x≤60\le x\le 6 as follows. • For 0≤x≤30\le x\le 3, f(x)=3f(x)=3 and g(x)=xg(x)=x. • For 3≤x≤63\le x\le 6, f(x)=6−xf(x)=6-x and g(x)=0g(x)=0. The graphs of ff and gg bound several regions in the plane. All questions below must be answered without evaluating any antiderivatives. (a) On the axes you create, sketch the graphs of y=f(x)y=f(x) and y=g(x)y=g(x) for 0≤x≤60\le x\le 6, clearly labeling all intercepts and intersection points. (b) Compute the exact area of the region where f(x)≥g(x)f(x)\ge g(x) on 0≤x≤30\le x\le 3. Explain how geometric formulas support your calculation. (c) Compute the exact area of the region where g(x)≥f(x)g(x)\ge f(x) on 3≤x≤63\le x\le 6. Justify your work geometrically. (d) Using your answers to parts (b) and (c), determine the numerical value of ∫06(f(x)−g(x)) dx\displaystyle\int_{0}^{6}\bigl(f(x)-g(x)\bigr)\,dx. Interpret the sign of this integral in the context of the regions you found.

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