Posted by Fadak on Friday, March 15, 2013 at 11:37am.
rate=changeinfunction/deltat as deltat >>0
rate=(8(t+h)(t+h+2))/h - 8(t(t+2)/h=
= 8/h * [(t^2+th+2t+ht+h^2+2h)-t^2+2t)
= 8/h * ( +2th+ +2h)
= 8 (2t+2)= 16(t+1)
and at t=a, then
ratechange=16(a+1)