Question

for the following exercises , write an explicit formula for each sequence,

Answer 1

4 , 7, 12 , 19 , 28....

Answer 2

please help ...

Answer 3

*NOT MY ANSWER*
https://answers.yahoo.com/question/index?qid=20120121184030AAuQ9fU
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An = A(n-1) + (2n-1)

A1 = 4
A2 = 4 + 3 = 7
A3 = 7 + 5 = 12
A4 = 12 + 7 = 19
A5 = 19 + 9 = 28
A6 = 28 + 11 = 39
A7 = 39 + 13 = 52
...

Answer 4

i dont get it

Answer 5

@directrix please help

Answer 6

I think it is neither a geometric nor arithmetic sequence.
Therefore, I am looking for a pattern.

From Alex's work, 3 is added to the first term to get the second.

Then, 5 is added to the second term to get the third term.

To get the explicit formula, the task is to find a relationship between the position number of a term and the value of the term.

For position 1, a_1 = 4

For position 2, a_2 = 7

I then looked a the sequence in this way:

1 1^2 + 3

2 2^2 + 3

3 3^2 + 3

4 4^2 + 3

5 5^2 + 3


That format produced the sequence terms.

Explicit term: a_n = n^2 + 3

Answer 7

is there a certain formula ?

Answer 8

If you want to know the 50th term in the sequence,

a_50 = the square of the position number 50 added to 3.

a_50 = 50^2 + 3

Answer 9

The explicit term is the formula for the nth term:

Explicit term: a_n = n^2 + 3

I don't know a formula for finding the nth term of this particular sequence.

I looked for a pattern.

Answer 10

There are nth term formulas for arithmetic and geometric sequences.

Answer 11

hmm.. well i got the first part but i have trouble determining the pattern

Answer 12

That requires patience and practice. The more of these you do, the better you get at it.

Answer 13

oh , how about this one 1 , 1 , 4/3 , 2 , 16/5 ....

Answer 14

I do not see that sequence as being geometric or arithmetic.

I rewrote the sequence to try to find a pattern;

1/1 , 2/2 , 4/3, 8/4 , 16/5 ,

Answer 15

The denominators are 1, 2, 3, 4, 5 which are the same as the position numbers.


1, 2, 4, 8, 16 (the numerators) are powers of what number?

The 1 may throw you off. If so, look at 2, 4, 8, 16. They are all powers of what number?

@marcelie

Answer 16

2 raised to what power = 2

2 raised to what power = 4

2 raised to what power = 8

2 raised to what power = 16

@marcelie

Answer 17

1, 2, 4, 8, 16

2^0 , 2^1, 2^2 , 2^3 , 2^4 numerators

The denominators are 1, 2, 3, 4, 5 which are the same as the position numbers.

Answer 18

Explicit term: a_n = 2^(n-1) / n