Use the position function feet to find the velocity at t = 3 seconds. (Round answer to 2 decimal places.)
A) v(3) = -5.44 ft/s
B) v(3) = -6.56 ft/s
C) v(3) = 6.56 ft/s
D) v(3) = -7.92 ft/s

Question

Use the position function  feet to find the velocity at t = 3 seconds. (Round answer to 2 decimal places.)
A) v(3) = -5.44 ft/s 
B) v(3) = -6.56 ft/s 
C) v(3) = 6.56 ft/s 
D) v(3) = -7.92 ft/s

Quizplus · Accepted Answer

To find velocity from position function, we take the first derivative of the function. So, if 
s(t) = 11eaa948_cd5e_7397_84bc_c9deee88dccd_TB2342_11 feet
then, 
v(t) = s'(t) = -2.72t^2 - 21.76t - 39.33 feet/second
Thus, the velocity at t=3 seconds would be
v(3) = -2.72(3)^2 - 21.76(3) - 39.33 = -5.44 ft/s (rounded to 2 decimal places)

Use the Position Function Feet to Find the Velocity