Solve Logarithmic Equation: 9_{x} + 3_{x} = \frac{4}{3}

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Homework Statement


9[tex]_{x}[/tex] + 3[tex]_{x}[/tex] = [tex]\frac{4}{3}[/tex]


Homework Equations



Solve the equation

The Attempt at a Solution


3[tex]_{2x}[/tex] + 3[tex]_{x}[/tex] = [tex]\frac{4}{3}[/tex]
I try to take ln for both sides ...? but how and there is a plus sign between them?
 
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the_storm said:

Homework Statement


9[tex]_{x}[/tex] + 3[tex]_{x}[/tex] = [tex]\frac{4}{3}[/tex]


Homework Equations



Solve the equation

The Attempt at a Solution


3[tex]_{2x}[/tex] + 3[tex]_{x}[/tex] = [tex]\frac{4}{3}[/tex]
I try to take ln for both sides ...? but how and there is a plus sign between them?

Taking the log of both sides won't do you any good since there's no way to simplify the log of a sum. You have a good start, though - just rewrite the equation as
[tex]3^{2x} + 3^{x} - \frac{4}{3} = 0[/tex]
This is quadratic in form. You can use micromass's suggestion or factor the equation as-is.