A particle moves in the plane with velocity vector v(t)=⟨f′(t),g′(t)⟩ for a≤t≤b. Which of the following procedures is MOST appropriate for identifying the time at which the particle attains its greatest speed on the interval [a,b]?
a) Set ∣v′(t)∣=0, then compare the resulting t–values with the endpoints.
b) Set f′′(t)=0 and g′′(t)=0, then test the resulting t–values and the endpoints.
c) Set s′(t)=0 where s(t)=∣v(t)∣, then compare those critical numbers with the endpoints.
d) Set f′(t)=0 and g′(t)=0, then test the resulting t–values and the endpoints.