Respuesta :

1.  The swimmer changes direction at t = 2.5 s

2. At t = 5, the instantaneous velocity of the swimmer is 5 ft/s

3. The acceleration of the swimmer is  2 ft/s²

1. How to find where the swimmer changes direction?

Since the swimmers position is given by s(t) = t² - 5t + 6, the swimmer changes direction at the critical point, that is when ds/dt = 0.

So, ds/dt = d(t² - 5t + 6)/dt

= dt²/dt - d5t/dt + d6/dt

= 2t - 5

So, ds/dt = 0 implies that

2t - 5 = 0

t = 5/2

t = 2.5 s

So, the swimmer changes direction at t = 2.5 s

2. The instantaneous velocity of the swimmer at t = 5 s.

Since the position of the swimmer is s(t) = t² - 5t + 6, his velocity is v = ds/dt = d(t² - 5t + 6)/dt

= dt²/dt - d5t/dt + d6/dt

= 2t - 5

At t = 5

v = 2t - 5

v = 2(5) - 5

v = 10 - 5

v = 5 ft/s

So, at t = 5, the instantaneous velocity of the swimmer is 5 ft/s

3. The acceleration of the swimmer

The acceleration of the swimmer is a = dv/dt

= d(2t - 5)dt

= d2t/dt - d5/dt

= 2 - 0

= 2 ft/s²

So, the acceleration of the swimmer is  2 ft/s²

Learn more about instantaneous velocity here:

https://brainly.com/question/24636214

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