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anonymous
 one year ago
Given the geometric sequence where a1 = 3 and the common ratio is 9, what is the domain for n?
anonymous
 one year ago
Given the geometric sequence where a1 = 3 and the common ratio is 9, what is the domain for n?

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anonymous
 one year ago
Best ResponseYou've already chosen the best response.0OPTIONS All integers All integers where n ≥ 1 All integers where n ≥ 1 All integers where n ≥ 0

SolomonZelman
 one year ago
Best ResponseYou've already chosen the best response.3Well, if you are starting from n=1, then your terms \(a_n\) can be: \(a_1\), \(a_2\), \(a_3\), \(a_4\),\(a_5\), and so forth.... To answers this question, you don't really need to know about the common ratio, or even what type of sequence it is. Nor do you have to know what the \(a_1\) is, as long as you know that is starts from \(a_1\) (i.e. from n=1).

SolomonZelman
 one year ago
Best ResponseYou've already chosen the best response.3All these: \(\large a_\color{red}{1}\), \(\large a_\color{red}{2}\), \(\large a_\color{red}{3}\), \(\large a_\color{red}{4}\), \(\large a_\color{red}{5}\), are values of n that are ?

SolomonZelman
 one year ago
Best ResponseYou've already chosen the best response.3Can you have \(\large a_{1}\) ??

SolomonZelman
 one year ago
Best ResponseYou've already chosen the best response.3yes, all positive integers, correct...

SolomonZelman
 one year ago
Best ResponseYou've already chosen the best response.3So your answer choice is c, n≥1.

SolomonZelman
 one year ago
Best ResponseYou've already chosen the best response.3Also I can teach you how to put up ≥ ≤ ∞ and other symbols without copy pasting, want to know how?

SolomonZelman
 one year ago
Best ResponseYou've already chosen the best response.3it works on almost every site...

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0Can you help me with this questions: Given the arithmetic sequence an = 3 + 9(n  1), what is the domain for n? OPTIONS: All integers where n ≥ 1 All integers All integers where n ≥ 0 All integers where n > 1

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0Is an arithmetic sequence always positive integers?

SolomonZelman
 one year ago
Best ResponseYou've already chosen the best response.3\(\large\color{blue}{ \displaystyle {\rm CODES,~~short~guide} }\) 1) Click and hold ALT 2) click the number code (using the numbers that are on the right of the keyboard, and `NOT` the ones below `F1`, `F2`, `F3`, etc., ) 3) release the ALT number code result `0 2 1 5 ` × `2 4 6 ` ÷ ` 7 ` • ──────────────── among with other symbols. code result 2 5 1 √ ` 7 5 4 ≥` 7 5 5 ≤ ` 2 4 1 or 7 5 3 ± ` 2 4 7 ≈ ` 0 1 8 5 ¹ ` 2 5 3 ² ` 0 1 7 9 ³ ` 1 6 6 ª ` 2 5 2 ⁿ ` 1 6 7 º ` 2 4 8 ° ` 0 1 5 3 ™ ` 0 1 9 0 ¾ ` 4 2 8 ¼ ` 1 7 1 ½ ` 2 2 7 π ` 1 5 5 ¢ ` 2 3 6 ∞ ` 1 5 9 ƒ `

SolomonZelman
 one year ago
Best ResponseYou've already chosen the best response.3Now as far as your question....

SolomonZelman
 one year ago
Best ResponseYou've already chosen the best response.3quoting your question: ``` Can you help me with this questions: Given the arithmetic sequence an = 3 + 9(n  1), what is the domain for n? OPTIONS: All integers where n ≥ 1 All integers All integers where n ≥ 0 All integers where n > 1 ``` (end quote) Now, you are given that \(\large\color{black}{ \displaystyle a_n=3+9(n1) }\)

SolomonZelman
 one year ago
Best ResponseYou've already chosen the best response.3it doesn't really tell you if it starts from \(a_0\) (i.e. from n=0), OR from \(a_1\) (i.e. from n=1). So, the only thing you can say for sure that it can't be option B (\(a_{n}\) doesn't exist).

SolomonZelman
 one year ago
Best ResponseYou've already chosen the best response.3basically, there is a lack of information here, without which I can't say anything.... I would assume though that they want you to say option C intuitively

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0Can you help me with the next question I have to do: What is the 9th term of the geometric sequence 4, 20, 100, ?

SolomonZelman
 one year ago
Best ResponseYou've already chosen the best response.3because they are proposing a thought that: "You can have first term, second term, third term, etc... something that is real (or tangible), BUT not zeroth term and certainly not negative term."

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0These are the options: 312,500 12,500 62,500 1,562,500

SolomonZelman
 one year ago
Best ResponseYou've already chosen the best response.3ok, so it starts from \(a_1=4\) Can you find the geometric ratio for me? (if not say idk, and I will guide you through this step)

SolomonZelman
 one year ago
Best ResponseYou've already chosen the best response.3Ok, a geometric ratio (r) in a sequence can be found using the following formula. \(\large\color{black}{ \displaystyle {\rm r}=\frac{a_{n}}{a_{n1}}}\) where \(\large\color{black}{ \displaystyle a_{n}}\) is any term in a sequence, and \(\color{black}{\large a_{n1}}\) is the term right before this \(\large\color{black}{ \displaystyle a_n}\). and "r" here, is of course the common ratio.  Btw, to make sure. Common ratrio is a number by which you multiply every/each time to obtain the nex term.

SolomonZelman
 one year ago
Best ResponseYou've already chosen the best response.3For example \(\large\color{black}{ \displaystyle {\rm r}=\frac{a_{2}}{a_1}}\) or \(\large\color{black}{ \displaystyle {\rm r}=\frac{a_{3}}{a_2}}\) or \(\large\color{black}{ \displaystyle {\rm r}=\frac{a_{4}}{a_3}}\) and on.... see?

SolomonZelman
 one year ago
Best ResponseYou've already chosen the best response.3now, how would you use the formula: \(\large\color{black}{ \displaystyle {\rm r}=\frac{a_{n1}}{a_n}}\) ? Which terms would you choose? (to answer my question consider the given information  which terms do you know already?)

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0the common ratio is .2 right?

SolomonZelman
 one year ago
Best ResponseYou've already chosen the best response.3\(\large\color{black}{ \displaystyle {\rm r}=\frac{a_{n}}{a_{n1}}}\) this si the formula

SolomonZelman
 one year ago
Best ResponseYou've already chosen the best response.3I made a typo in my previous reply, but the rest of information is right

SolomonZelman
 one year ago
Best ResponseYou've already chosen the best response.3so, for example \(\large\color{black}{ \displaystyle {\rm r}=\frac{a_{2}}{a_1}~~~~~\Rightarrow {\small \rm (in~this~case)~}~~~~ {\rm r}=\frac{20}{4}=?~~~{\small \rm (you~tell~me)}}\)

SolomonZelman
 one year ago
Best ResponseYou've already chosen the best response.3yes, r=5. ``` Side Note: Sometimes I will be typing stuff while you are typing, and if that is the case don't be afraid to interrupt... keep typing:) ```

SolomonZelman
 one year ago
Best ResponseYou've already chosen the best response.3Ok, have you ever seen a formula \(\large\color{blue}{ \displaystyle a_n=a_1 \cdot {\rm r}^{n1}}\) ?

SolomonZelman
 one year ago
Best ResponseYou've already chosen the best response.3ok, w will show what it i and how it works (if you don't mind)

SolomonZelman
 one year ago
Best ResponseYou've already chosen the best response.3in GEOMETRIC sequence: in order to obtain \(a_2\) you have to multiply \(a_1\) times the common ratio r. That is: \(a_1 \times {\rm r} = a_2\) correct?
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