Question

If a ball is thrown into the air with a velocity of 42 ft/s, its height (in feet) after t seconds is given by y = 42t − 16t2. Find the velocity when t = 1.

Answer 1

y = 42t - 16t^2

velocity = vt = dy/dt

= 42 - 32t

v(1) = 42 - 32

= 10 ft/s

Hope this helps