Find all values of x which satisfy the inequality

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To solve the inequality 6^(2x+3) < 2^(x+7) * 3^(3x-1), the initial approach involved rewriting the equation to align the bases. By expressing the right-hand side with a common exponent, it simplifies to 6^(2x+3) * (3/2)^(x-4). Taking logarithms can also aid in solving the inequality, but the rewritten form makes it more manageable. The discussion emphasizes the importance of aligning the bases for easier comparison. Ultimately, the goal is to find all values of x that satisfy the inequality.
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6^(2x+3) < 2^(x+7) * 3^(3x-1)

So what i did first was:

3^(2x+3) * 2^(2x+3) < 2^(x+7) * 3^(3x-1)

Now i don't know how to set up the equation. I guess this is not correct

2*(2x+3) < x+7 + 3x - 1
 
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First of all, what is it that you're trying to do? Find for which x this is true? Show that it is always true? Show that it is never true?
 
Find all values of x which satisfy the inequality. Sorry i didnt mention, i thought it was clear.
 
Petkovsky said:
6^(2x+3) < 2^(x+7) * 3^(3x-1)

Hi Petkovsky! :smile:

Hint: take logs. :wink:
 
We needn't even take logs, the numbers happen to work out very nicely =]

Q: Find x such that; 6^{2x+3} &lt; 2^{x+7} \cdot 3^{3x-1}.

Rewrite the exponents on the RHS to also have 2x+3's, RHS = \frac{2^{2x+3}}{2^{x-4}} \cdot 3^{2x+3} 3^{x-4} = 6^{2x+3} \left( \frac{3}{2} \right)^{ x-4}.

The question is much easier in this form.
 
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