For any real number n, Sn = 2 ^ n-1, then A1 ^ 2 + A2 ^ 2 + a3 ^ 2 +... + an ^ 2 is equal to?

For any real number n, Sn = 2 ^ n-1, then A1 ^ 2 + A2 ^ 2 + a3 ^ 2 +... + an ^ 2 is equal to?

an=Sn-S(n-1)
=2^n-2^(n-1)
=2^(n-1)
an²=4^(n-1)
So an & # 178; or an equal ratio sequence, q = 4
So the original formula = 1 * (4-4 ^ n) / (1-4) = (4 ^ n-1) / 3

Elden Ring Premiere

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