The position of an object moving along a line is given by p(t) = 2t - t^2cos(( pi )/3t) . What is the speed of the object at t = 5 ?

1 Answer
Apr 21, 2016

p(t) = 2t - t^2cos(pi/3t)

The speed is given as:

v(t) = dotp(t) = 2+2pi/3tsin(pi/3t)

so,

v(5) = 2+(2pi)/3*5*sin((5pi)/3) ~~ 2 +(2pi)/3*5*(-0.87) = -7.11