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Thus,
R(t) = e
−λt
which is the familiar exponential reliability function. Both F(t) and R(t) are
shown in Figure 11.4.
Clearly, any one of the functions f(t), F(t), or R(t) may be dened in
terms of the others. If T is the random variable representing the yet-to-be-
observed time to failure, then any one of these functions gives a complete
description of our uncertainty about T. For example,
where P stands for the probability function. e equation tells us that the
probability that the actual time to failure will be greater than a given time
t is equal to R(t) or 1 − F(t). us, having any one of ...