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

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Homework Statement


9_{x} + 3_{x} = \frac{4}{3}


Homework Equations



Solve the equation

The Attempt at a Solution


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

Homework Statement


9_{x} + 3_{x} = \frac{4}{3}


Homework Equations



Solve the equation

The Attempt at a Solution


3_{2x} + 3_{x} = \frac{4}{3}
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
3^{2x} + 3^{x} - \frac{4}{3} = 0
This is quadratic in form. You can use micromass's suggestion or factor the equation as-is.
 
thank you guys done :) :)
 
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