Can you help me to find the solution of logarithm equation

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Homework Help Overview

The discussion revolves around solving the logarithmic inequality $$\log_2 \sqrt{2x-1} < \log_4 x$$. Participants are attempting to manipulate the inequality and clarify the logarithmic properties involved.

Discussion Character

  • Exploratory, Conceptual clarification, Mathematical reasoning

Approaches and Questions Raised

  • Some participants are attempting to rewrite the logarithmic expressions and simplify the inequality. Others are questioning the correctness of the initial setup and the notation used, particularly regarding parentheses and logarithm bases.

Discussion Status

The discussion is ongoing, with participants providing feedback on each other's attempts. Some guidance has been offered regarding the rewriting of logarithmic terms, but there is no explicit consensus on the correct approach or solution yet.

Contextual Notes

There appears to be confusion regarding the notation and the logarithm base, which may be affecting the clarity of the problem. Additionally, the late hour is noted as a factor in the participants' ability to follow the discussion.

Helly123
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Homework Statement


$$\log_2 \sqrt{2x-1} < \log_4 x$$

Homework Equations

The Attempt at a Solution


$$\log_2 \sqrt{2x-1} < \log_4 x$$
$$\log_2 {2x-1}^{1/2} < \log_2 \sqrt{x}$$
$$1/2 \log_2 {(2x-1)} - \log_2 \sqrt{x} < 0$$
$$ 1/2 \log_2 {\frac{(2x-1)}{ x}} < 0$$
$$ -1/2 \log_2 {(2x-1) x} < 0$$
$$ 1/2 \log_2 {(2x^2-x)} > 0$$
$$ \log_2 {\sqrt{(2x^2-x)}} >\log_2 {1} $$
$$2x^2 - x > 1$$
$$2x^2 - x - 1 = 0$$
$$(2x + 1)(x -1) = 0$$
$$x < -1/2 \ \ or \ \ x > 1$$

but I get wrong answers. How to find the right answer? can you help me?
 
Last edited:
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Helly123 said:

Homework Statement


$$\log_2 \sqrt{2x-1} < \log_4 x$$

Homework Equations

The Attempt at a Solution


$$\log_2 {2x-1}^{1/2} < \log_2 \sqrt{x}$$
You miss parentheses on the left side and the base of logatrithm is 4 instead of 2 on the right side.
 
ehild said:
You miss parentheses on the left side and the base of logatrithm is 4 instead of 2 on the right side.
That's exactly what the question is..
 
Helly123 said:
That's exactly what the question is..
No. The question is :
##
\log_2 \sqrt{2x-1} < \log_4 x##
 
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I can't really follow all your steps because it's almost 2am over here and it's been a long day. However, your second line can be written as

##\frac12 \log_2(2x - 1) < \frac12 \log_2(x)##

from here it should be solved in 3 steps
 
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ehild said:
No. The question is :
##
\log_2 \sqrt{2x-1} < \log_4 x##
ive changed it
 
Marc Rindermann said:
I can't really follow all your steps because it's almost 2am over here and it's been a long day. However, your second line can be written as

##\frac12 \log_2(2x - 1) < \frac12 \log_2(x)##

from here it should be solved in 3 steps
I see.. that's true. Thank you
 

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