Gwen runs back and forth along a straight track. During the time interval 0≤t≤45 seconds, Gwen’s...

Gwen runs back and forth along a straight track. During the time interval 0≤t≤45 seconds, Gwen’s velocity, in feet per second, is modeled by the function v given by v(t)=(250sin(t^2/120))/(t+6).

(a) What is the first time, t1, that Gwen changes direction? Find Gwen’s average velocity over the time interval 0≤t≤t1.

(b) At time t=45 , how far is Gwen from her position at time t=0 ?

(c) Find the total distance that Gwen runs during the 45 seconds from time t=0 to time t=45 .

Expert Solution

Dear student,

In order to find the position were the direction has changed you have consider the time were velocity is zero.

Similarly, if you were asked to find the position where velocity changes its direction you need to take the position were acceleration is zero.

Colby Messinger answered 2 years ago

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