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# Help with geometric sequences watch

1. Table shows the number of bacteria present in a particular sample for the first 5 minutes

Time Bacteria present
0 2
1 4
2 8
3 16
4 32
5 64

Note: The 0,1,2,3,4,5 is time and other figures are bacteria. I couldn't make a table properly.

Use Algebra to extend this model for the growth of bacteria colonies with following conditions:
The relationship between the number of bacteria and the size of the colony and ;Different rates of replication

Hi guys i am stuck at this question as i dont know in what way i should be extending the model. Please share your insights about how to tackle this question.

F(t) = 2^t+1 or 2(2)^t
2. (Original post by Jyashi)
Table shows the number of bacteria present in a particular sample for the first 5 minutes

Time Bacteria present
0 2
1 4
2 8
3 16
4 32
5 64

Note: The 0,1,2,3,4,5 is time and other figures are bacteria. I couldn't make a table properly.

Use Algebra to extend this model for the growth of bacteria colonies with following conditions:
The relationship between the number of bacteria and the size of the colony and ;Different rates of replication

Hi guys i am stuck at this question as i dont know in what way i should be extending the model. Please share your insights about how to tackle this question.
Well, you first want to express

You can see that (calling B the number of bacteria) , where is some function of you need to find. It's pretty easy, exponential.
Spoiler:
Show
.
3. (Original post by Zacken)
Well, you first want to express

You can see that (calling B the number of bacteria) , where is some function of you need to find. It's pretty easy, exponential.
Spoiler:
Show
.
Thank you for your answer. already knew the function is (2)^t+1 as i also know it can also be 2(2)^t

But i dont know what to do after this.
4. (Original post by Jyashi)
Thank you for your answer. already knew the function is (2)^t+1 as i also know it can also be 2(2)^t

But i dont know what to do after this.
As it stands your question is missing information, why don't you post a picture of your question so we can better help you? (THE FULL QUESTION)

Also, by the law of indices.
5. (Original post by Zacken)
As it stands your question is missing information, why don't you post a picture of your question so we can better help you? (THE FULL QUESTION)

Also, by the law of indices.
6. (Original post by Jyashi)
Table shows the number of bacteria present in a particular sample for the first 5 minutes

Time Bacteria present
0 2
1 4
2 8
3 16
4 32
5 64

Note: The 0,1,2,3,4,5 is time and other figures are bacteria. I couldn't make a table properly.

Use Algebra to extend this model for the growth of bacteria colonies with following conditions:
The relationship between the number of bacteria and the size of the colony and ;Different rates of replication

Hi guys i am stuck at this question as i dont know in what way i should be extending the model. Please share your insights about how to tackle this question.

F(t) = 2^t+1 or 2(2)^t
So you have a series You should see that this is clearly a geometric progression with first term and common ratio . The amount of bacteria present at any time t is given by

The rate of growth is given by the rate of change of bacteria with respect to time .

If we started with a different number at time = 0 then we could adapt the model by letting the first term a be generic, so . This would mean
I think this is what the question is getting at however I'm not 100% sure.
7. (Original post by Louisb19)
So you have a series You should see that this is clearly a geometric progression with first term and common ratio . The amount of bacteria present at any time t is given by

The rate of growth is given by the rate of change of bacteria with respect to time .

If we started with a different number at time = 0 then we could adapt the model by letting the first term a be generic, so . This would mean
I think this is what the question is getting at however I'm not 100% sure.
That would be because it isn't a question per se, more like a project that involves real data researcg, etc...

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