Difficult logarithm question

IBstudent

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Hello!

Attached is a math question that I couldn't solve during a test, I would really appreciate it if anyone can show me the method to solve it :)

Thanks in advance
 
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You were correct by multiplying by \(\displaystyle 5^{x}\).

\(\displaystyle 2\cdot 5^{2x+1}=5^{x}+3\)

\(\displaystyle 10\cdot 5^{2x}-5^{x}-3=0\)

Now, it is a quadratic by letting \(\displaystyle u=5^{x}\)

\(\displaystyle 10u^{2}-u-3=0\)

This factors. There is one extraneous solution....the negative one.

Can you finish now?.
 
The picture can be enlarged by clicking on it.

You were correct by multiplying by \(\displaystyle 5^{x}\).

\(\displaystyle 2\cdot 5^{2x+1}=5^{x}+3\)

\(\displaystyle 10\cdot 5^{2x}-5^{x}-3=0\)

Now, it is a quadratic by letting \(\displaystyle u=5^{x}\)

\(\displaystyle 10u^{2}-u-3=0\)

This factors. There is one extraneous solution....the negative one.

Can you finish now?.

Yip :D

Thanks alot for your help
 
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