Homework Help!

sizzlingkavya

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Dec 3, 2009
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16
Question - 1: - Find the exponential function f(x)=c . 2^{b x} whose graph is (0,2) & (1,3). Find the value of a & b

I have find a & the ans is 2 but I am not getting the right answer of b so please tell me the answer of b

Question - 2: - A bacteria culture initially contains 2500 bacteria and doubles every half hour. The formula for the population is p(t)=2500 e^{kt} for some constant k. (You will need to find k to answer the following.)

Find the size of the baterial population after 80 minutes. ______________

Find the size of the baterial population after 4 hours. ______________

after solving these I have got 11088 for the first one & 639246.8 for the second one but these are not the right answer. Please help me to find the right answers of these questions.
 
In Q1, did you mistype "c" instead of "a" ?

If so, then (2)2[sup:p51wezf8]b[/sup:p51wezf8]=3, 2[sup:p51wezf8]b+1[/sup:p51wezf8]=3, b+1=log[sub:p51wezf8]2[/sub:p51wezf8]3

b=(log[sub:p51wezf8]2[/sub:p51wezf8]3)-1.

check that first.

Then you can convert it to log[sub:p51wezf8]e[/sub:p51wezf8] after that.
 
This is also wrong. How can I convert log value. I am not good in log at all, so please help me.
 
You can think of logs and powers as being inverses.
Addition and subtraction are inverses, so are multiplication and division etc.
It can take a while to master logs,
many students do not find them easy to learn.

2[sup:1bz7i0tb]3[/sup:1bz7i0tb]=8, now slide the 2 over so it is under the 8 to the left and write the log
3=log[sub:1bz7i0tb]2[/sub:1bz7i0tb]8
Now imagine sliding the 2 back again and remove the log to get 2[sup:1bz7i0tb]3[/sup:1bz7i0tb]=8
or 10[sup:1bz7i0tb]3[/sup:1bz7i0tb]=1000,
so 3=log[sub:1bz7i0tb]10[/sub:1bz7i0tb]1000
or e[sup:1bz7i0tb]x[/sup:1bz7i0tb]=y,
so x=log[sub:1bz7i0tb]e[/sub:1bz7i0tb]y.

We are writing "power" = log(value)

First, can you check the original equation, see the question I asked earlier.
Also are you being asked to express your answer using e[sup:1bz7i0tb]x[/sup:1bz7i0tb] ?
 
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