We can use the exponential distribution formula to solve this problem:
P(X > 8) = e^(-λx)
where X is the time between repairs, λ is the rate parameter (1/1 = 1), and x is the time we are interested in (8 years).
P(X > 8) = e^(-1*8) = e^(-8) = 0.00033546
Therefore, the probability that the appliance will work at least eight years without requiring repairs is approximately 0.00033546, or about 0.0335%.