Let the mean and the variance of 20 observations x1,x2,…x20 be 15 and 9, respectively. For α∈R, if the mean of (x1+α)2,(x2+α)2,…,(x20+α)2 is 178, then the square of the maximum value of α is equal to ______.
Held on 29 Jul 2022 · Verified 6 Jul 2026.
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