Sequence 3 / 2,1,5 / 8,3 / 8 The general term formula an =?

Sequence 3 / 2,1,5 / 8,3 / 8 The general term formula an =?

Change the denominator to 8
12/8,8/8,5/8,3/8
The law of molecules 12,8,5,3
It's strange if the title is wrong
If the last term is 2, then an = (15-3n) / 8
Observe, the numerator is 3, 4, 5, 6, and the denominator is 2, 4, 8, 16
An=(n^2-11n+34)/16
General observation, general score, addition, subtraction, multiplication and division. Do you have any rules?
If we can't find it, and it's a limited data, we can assume an = xn ^ 2 + yn + Z
If you bring in the known data, you can get the
Well, there's nothing I can do about this problem. I'm just a junior high school student...
(a+b)÷(a^2-b^2) （x^2+2x+1）÷(x^2+x) (3x-6)÷（x^2-4x+4） 3x÷（6x^2z）
About
(a+b)/(a+b)(a-b)=a-b
(x+1)^2/x(x+1)=x+1
3 X-2
2XZ
To find the general term formula of a sequence of numbers
It is known that the sequence {an} satisfies a (n) = 2A (n-1) + 2 ^ n-1 (n ∈ n + and N ≥ 2) (the angle in brackets is shown in the figure below),
And a (1) = 5, a (2) = 13, a (3) = 33, a (4) = 81
General term formula for an
[Note: the method of formal answer is required, which can't be set by incomplete induction according to the previous items]
By subtracting 1 from both sides, we get a (n) - 1 = 2 [a (n-1) - 1] + 2 ^ n
Then divide the two sides by 2 ^ n to get the arithmetic sequence of {[a (n) - 1] / 2 ^ n} with the first term of 2 and d = 1,
We can calculate a (n) = (n + 1) * 2 ^ n + 1
3x/6x^2z a+b/a^2-b^2 x^2+2x+1/x^2+x 3x-6/x^2-4x+4
3x/6x^2z
a+b/a^2-b^2
x^2+2x+1/x^2+x
3x-6/x^2-4x+4
y-x/x^2-y^2
2x^2-10x/x^2-10x+25
Approximately:
3x/6x^2z
a+b/a^2-b^2
x^2+2x+1/x^2+x
3x-6/x^2-4x+4
y-x/x^2-y^2
2x^2-10x/x^2-10x+25
3x/6x^2z =1/2xza+b/a^2-b^2=(a+b)/(a+b)(a-b)=1/(a-b)x^2+2x+1/x^2+x=(x+1)²/x(x+1)=(x+1)/x3x-6/x^2-4x+4=3(x-2)/(x-2)²=3/(x-2)y-x/x^2-y^2=-(x-y)/(x+y)(x-y)=-1/(x+y)2x^2-10x/x^2-10x+25=2x(x-5)/(x...
Mathematical problems in Vocational High Schools -- general formula of sequence
According to the first five terms of the following infinite series, write a general term formula of the series
（1）2,2,2,2,2…… （2）-1,1/8,-1/27,1/64,-1/125……
（3）3/5,4/8,5/11,6/14,7/17……
I hope there will be a process, because I won't do it at all
① An = 2 (this is a constant column) without looking at the sign, we find a rule: 1 / 8 = 1 / 2 & # 179;, 1 / 27 = 1 / 3 & # 179;, 1 / 64 = 1 / 4 & # 179 Look at the sign again. The first is negative, the second is positive The odd number is negative and the even number is positive
(6x + 1) (4x + 1) (3x + 1) (2x + 1) = 41x ^ 2 velocity,
(6x + 1) (4x + 1) (3x + 1) (2x + 1) = 41x ^ 2 (6x + 1) (2x + 1) (4x + 1) (3x + 1) = 41x ^ 2 (12x ^ 2 + 8x + 1) (12x ^ 2 + 7x + 1) = 41x ^ 2 (12x ^ 2 + 1) ^ 2 + 15x (12x ^ 2 + 1) + 56x ^ 2 = 41x ^ 2 (12x ^ 2 + 1) ^ 2 + 15x (12x ^ 2 + 1) + 15x ^ 2 = 0
In mathematics, how many terms of a sequence can be given to determine the unique general term formula?
Generally, three to five terms can be used to infer the general term formula. The questions we usually do must be proved according to the corresponding format. Mathematics is rigorous, and the general term formula usually needs to be proved, not by giving a few items
Two items, the number of items is given
As long as there are rules,
Given that the value of 2x ^ + 3x is 82, find the value of - 4x ^ - 6x + 9
-4x^-6x+9
=-2（2x^+3x）+9
=-2*82+9
=-164+9
=-155
-4x^-6x+9=-2(2X^2+3X)+9=-2*82+9=155
2x^2+3x=82
-4x^-6x+9=-2(2x^2+3x)+9
=-82*2+9
=-155
Several questions about the general term formula of sequence of numbers
1. If the sequence {an} satisfies a (n + 1) = (n + 1 / N) * an, A1 = 2, find the general term formula an
2. If the sequence {an} satisfies a (n + 1) = 2An + 2 ^ (n + 1), A1 = 1, find the general term formula an
3. If the sequence {an} satisfies a (n + 1) = an ^ 3 and A1 = 6, find the general term formula an
Back to hpxlsxr: points are certainly not a problem
I'm good at general terms. (1) there are two ways to use cumulative multiplication. (2) one is to divide left and right by 2 ^ (n + 1), two is to determine coefficient method, and (3) is to take logarithm. If you promise me, I'll work out the detailed process
2x+5/2=4x+3/4-2-3x/8
2x+5/2=4x+3/4-2-3x/8
13/8x=1/4
x=2/13
2x+5/2=4x+3/4-2-3x/8
Multiply both sides by eight at the same time, and you get
4(2x+5)=2(4x+3)-(2-3x)
8x+20=8x+6-2+3x
-3x=4-20
-3x=-16
x=16/3