Question

f(t)= 1+.9e^(-.02t) with t ≥ 0 show that function is decreasing for all t values

Answer 1

f'(t)=-0.02*0.9e^(-0.02t)=-0.018e^(-0.02t)
Since e^(t) > 0 for all -inf < t < +inf, so
f'(t) < 0 for all -inf < t < +inf, i.e. f(x) is strictly decreasing for all t in R

Answer 2

thank you!!

Answer 3

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