# Another P2 logs question

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16 years ago
#1
3^(2x+1) = 3^x + 24

Any help would be much appreciated!
Thanks!
xxx
0
16 years ago
#2
ok...

3^(2x + 1) is the same as 3^x * 3^x * 3^1

So 3^x * 3^x * 3 = 3^x + 24

Now let y = 3^x to simplify it a bit

Then we have:

3y^2 = y + 24

From there form a quadratic = 0 and solve to get

y = 3 or y = -8/3

But y = 3^x, so either 3^x = 3 ---> x = 1

or 3^x = -8/3 ---> No real solution

So x = 1, and if you check:

3^3 = 3 + 24

27 = 3 + 24
0
16 years ago
#3
Thank you so much!
I was getting confused over the + 1 part of the first power, but I understand now!
Cheers mate!
xxx
0
16 years ago
#4
no problem
0
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