Question 28346
Differenitate:
{{{dy/dx=-16^2+269}}}
=-32x
Lim(-32x) ---> -32(3)=-96
x->3


a) HENCE, the rock's velocity is -96 at 3 second.


b) {{{-16x^2=-269}}}
{{{x^2=16.8125}}}
x=4.1


Hence, it takes the rock about 4.1 seconds to hit the ground.
Paul.