Known sequence (an) satisfies: A1 = 1,2 ^ (n-1) * an = a subscript (n-1) (n is a positive integer), n ≥ 2 (1) to find the general term formula of sequence (an) Known sequence (an) satisfies: A1 = 1,2 ^ (n-1) * an = a subscript (n-1) (n is a positive integer), n ≥ 2 (1) Finding the general term formula of sequence (an) (2) The number sequence is less than 1 / 1000 from the beginning

Known sequence (an) satisfies: A1 = 1,2 ^ (n-1) * an = a subscript (n-1) (n is a positive integer), n ≥ 2 (1) to find the general term formula of sequence (an) Known sequence (an) satisfies: A1 = 1,2 ^ (n-1) * an = a subscript (n-1) (n is a positive integer), n ≥ 2 (1) Finding the general term formula of sequence (an) (2) The number sequence is less than 1 / 1000 from the beginning

(1) 2 ^ (n-1) * an = a (n-1), then a (n-1) / an = 2 ^ (n-1), then (A1 / A2) * (A2 / A3) *... * [a (n-1) / an] = A1 / an = 2 * (2 ^ 2) *... * [2 ^ (n-1)] = 2 ^ [1 + 2 +... + (n-1)] = 2 ^ {[1 + (n-1)] * n / 2} = 2 ^ [(n ^ 2) / 2], because A1 = 1, substituting the above formula, an = 2 ^ [- (n ^ 2) / 2] (2) has an = 1 / {2 ^ [...]

The root of equation X3 + lgx = 18 is x =?
The title is about and so on, I will not type about and so on.. the request is accurate to 0.1
thank you

Because 2.6 ^ 3 = 17.5760, 2.7 ^ 3 = 19.68 and LG (2.6) is about equal to LG (2.7) is less than 0.5, so x is about 2.6

Find the approximate solution of equation X3 + lgx = 18

Because 2.6 ^ 3 = 17.5760, 2.7 ^ 3 = 19.68 and LG (2.6) is about equal to LG (2.7) is less than 0.5, so x is about 2.6

The sequence {an} belongs to N + for all natural numbers n, satisfying a1 + 2A2 + 22a3 +... + 2n-1an = 9-6n, finding the general term formula of {an}

Let's find the general term formula of an for all natural numbers n ∈ n +, satisfying a1 + 2A2 + 2 ^ 2A3 +. + 2 ^ (n-1) an = 9-6n. [solution] a1 + 2A2 + 2 ^ 2A3 +. + 2 ^ (n-2) an-1 + 2 ^ (n-1) an = 9-6n replace n with n-1 to get a1 + 2A2 + 2 ^ 2A3 +. + 2 ^ (n-2) an-1 = 9-6 (n-1) up and down to get 2 ^ (n-1) a

Given that the sequence {an} satisfies an + 1 = 2An + 3 * 2 ^ n, A1 = 2, the general term formula of sequence {an} can be obtained by definition method
There must be a definition (⊙ o ⊙) oh
Note: N and N + 1 next to a are subscripts

It can be concluded from the original formula that the n-th power of an + 1 / 2 = the n-th power of an / 2 + 3
That is, the power of an + 1 / 2 to the nth power - the power of an / 2 to the nth power = 3
Then, let an / B1 = 2
And BN + 1-bn = 3
So BN is an arithmetic sequence with 2 as the first term and 3 as the tolerance
So BN = 3n-1
That is, the N-1 power of an = 2 * (3n-1)