We saw above that
R(t+h) - R(t)

h
=
500 - 200t - 100h
.
Letting h 0 gives
R'(t) =
lim
h0
R(t+h) - R(t)

h
=
lim
h0		 [500 - 200t - 100h]
=500 - 200t
since as h approaches 0, the quantity 100h approaches 0 as well.

Enter this as 500-200*t     or     500-200t

 

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