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Starting at the same time and place, Abe and Bob race, running at velocities

u(t)=4/t+1 and v(t)=4e⁻ᵗ/² mi/hr, respectively, for t⩾0
. Who is ahead after t=5hr ?

1 Answer

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Final answer:

To find who is ahead after 5 hours, integrate the velocity functions of Abe and Bob over the interval from t=0 to t=5, and compare the distances traveled. The runner with the greater distance will be the one ahead.

Step-by-step explanation:

The student asks who will be ahead after t=5 hours if Abe and Bob race starting at the same time and place, with Abe running at velocity u(t)=4/(t+1) and Bob running at velocity v(t)=4e⁻¹¹/2 mi/hr. To determine who is ahead, we calculate the distance each runner has traveled by the time t=5 hours by integrating their velocity functions with respect to time.

For Abe: distance = ∫ u(t) dt = ∫ (4/(t+1)) dt from t=0 to t=5.

For Bob: distance = ∫ v(t) dt = ∫ (4e⁻¹¹/2) dt from t=0 to t=5.

After evaluating these integrals, we obtain the total distance ran by each runner. The runner with the larger distance will be ahead after 5 hours.

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