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Solve 2log_5 (sqrt(x))−log_5 (6x−1)=0.

User Synergetic
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Final answer:

The logarithmic equation 2log_5 (sqrt(x)) - log_5 (6x-1) = 0 simplifies to log_5 (x/(6x-1)) = 0. Further simplification using logarithmic properties leads to the quadratic equation 5x-1 = 0, which has a solution of x = 1/5. Verification of the solution within the domain of the original logarithms is recommended.

Step-by-step explanation:

To solve the logarithmic equation 2log_5 (sqrt(x)) − log_5 (6x−1) = 0, we first utilize the logarithmic property that allows us to combine logs by division when they are subtracted: log_a - log_b = log(a/b). Using this property, we can rewrite the given equation as:

log_5 ((sqrt(x))^2/(6x−1)) = 0

We know that (sqrt(x))^2 = x, thus simplifying the expression inside the log:

log_5 (x/(6x−1)) = 0

Using the property that log_b(a) = c means b^c = a, we can rewrite this equation as:

5^0 = x/(6x−1)

As any number raised to the power of 0 is 1, this gives us:

1 = x/(6x−1)

Now we can solve for x by cross-multiplying and moving all terms to one side to get a quadratic equation:

6x−x−1 = x

Which simplifies to:

5x−1 = 0

Adding 1 to both sides and then dividing by 5 gives us:

x = 1/5

The student should verify that the solution is in the domain of the original logarithmic functions.

User Abgregs
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