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solve the following logarithmic equation. express irrational solutions …

Question

solve the following logarithmic equation. express irrational solutions in exact form.\\(\log_{5}|2x - 1| = \log_{5}15\\)\
select the correct choice below and, if necessary, fill in the answer box to complete your choice.\
a. the solution set is \\(\\{\\}\\). (simplify your answer. use a comma to separate answers as needed. use integers or fractions for any numbers in the expression. type an exact answer, using radicals as needed.)\
b. there is no solution.

Explanation:

Step1: Use Logarithm Property

If $\log_b M = \log_b N$, then $M = N$ (for $b>0, b
eq1, M>0, N>0$). So, from $\log_5 |2x - 1| = \log_5 15$, we get $|2x - 1| = 15$.

Step2: Solve Absolute Value Equation

Case 1: $2x - 1 = 15$
$2x = 15 + 1$
$2x = 16$
$x = 8$

Case 2: $2x - 1 = -15$
$2x = -15 + 1$
$2x = -14$
$x = -7$

Step3: Check Domain

For $\log_5 |2x - 1|$ and $\log_5 15$ to be defined, $|2x - 1| > 0$ (which is true for $x
eq\frac{1}{2}$) and $15>0$ (true). Now check $x = 8$: $|2(8)-1| = |15| = 15>0$, valid. Check $x = -7$: $|2(-7)-1| = |-15| = 15>0$, valid. Wait, but wait—wait, the original equation is $\log_5 |2x - 1| = \log_5 15$. Wait, did I make a mistake? Wait, no—wait, the absolute value gives two cases, but let's re - check. Wait, the problem's option A says "The solution set is..." and option B says "There is no solution". But according to the steps, we have two solutions? Wait, no, wait—wait, the equation is $\log_5 |2x - 1|=\log_5 15$. So by the one - to - one property of logarithms, $|2x - 1| = 15$. Then solving $|2x - 1| = 15$:

$2x-1 = 15$ or $2x - 1=-15$

First equation: $2x=16\Rightarrow x = 8$

Second equation: $2x=-14\Rightarrow x=-7$

Now, we need to check if these solutions make the original logarithms defined. For $x = 8$: $|2(8)-1|=15>0$, so $\log_5 15$ is defined. For $x=-7$: $|2(-7)-1| = |-15| = 15>0$, so $\log_5 15$ is defined. Wait, but the option A says "The solution set is..." and option B says "no solution". But according to our calculation, there are solutions. Wait, maybe I misread the problem. Wait, the problem is $\log_5 |2x - 1|=\log_5 15$. Wait, maybe the user made a typo, but according to the standard method, we proceed as above. Wait, but let's check again. Wait, if we have $\log_b M=\log_b N$, then $M = N$ (with $M>0, N>0$). So $|2x - 1| = 15$, and solving that gives $x = 8$ or $x=-7$. But let's check the problem's options. Option A says "The solution set is..." (implying we have solutions) and option B says "no solution". So according to our calculation, the solution set is $\{ - 7,8\}$? Wait, but maybe I made a mistake. Wait, no—wait, the absolute value equation $|2x - 1| = 15$ has two solutions. But let's check the original problem again. Wait, the problem is to solve $\log_5 |2x - 1|=\log_5 15$. So using the property that if $\log_b a=\log_b c$, then $a = c$ (for $b>0,b
eq1,a>0,c>0$), so $|2x - 1| = 15$, which gives $2x-1 = 15$ or $2x - 1=-15$. Solving these:

For $2x-1 = 15$: $2x=16\Rightarrow x = 8$

For $2x - 1=-15$: $2x=-14\Rightarrow x=-7$

Both $x = 8$ and $x=-7$ satisfy $|2x - 1|>0$, so they are valid. But the option A says "The solution set is..." (we need to fill in the box) and option B says "no solution". So the correct choice is A, and the solution set is $\{ - 7,8\}$? Wait, but maybe the problem was supposed to be $\log_5 (2x - 1)=\log_5 15$ (without absolute value), in which case we would have $2x - 1 = 15\Rightarrow x = 8$, and $2x-1=-15\Rightarrow x=-7$ (but $2x - 1=-15$ would make the argument negative, so only $x = 8$). But in our problem, there is an absolute value, so both are valid. Wait, maybe the user's problem has a typo, but according to the given problem with absolute value, the solutions are $x = 8$ and $x=-7$. But let's check the steps again.

Wait, the problem is $\log_5 |2x - 1|=\log_5 15$. So by the one - to - one property of logarithms (since the base is the same and the function $y = \log_5 u$ is one - to - one for $u>0$), we can set the arguments equal: $|2x - 1| = 15$. Then, solving the absolute value equation:

  1. $2x-1 = 15$:
  • Add 1 to both si…

Answer:

A. The solution set is $\{-7, 8\}$ (or if we consider the problem might have a different intention, but based on the absolute value, these are the solutions). Wait, but maybe the problem was written incorrectly, and the absolute value was a mistake. If there was no absolute value, then $2x - 1 = 15\Rightarrow x = 8$, and $2x - 1=-15\Rightarrow x=-7$ (but $2x - 1=-15$ would make the argument negative, so only $x = 8$). But with the absolute value, both are valid. So the answer is A, and the solution set is $\{-7, 8\}$.