What is the true solution to the equation below?

[tex]\[ 2 \ln e^{\ln (2x)} - \ln e^{\ln (10x)} = \ln 30 \][/tex]

A. [tex]\(x = 30\)[/tex]

B. [tex]\(x = 75\)[/tex]

C. [tex]\(x = 150\)[/tex]

D. [tex]\(x = 300\)[/tex]



Answer :

To find the true solution to the equation:

[tex]\[ 2 \ln (e^{\ln 2 \cdot x}) - \ln (e^{\ln 10 \cdot x}) = \ln 30 \][/tex]

we will simplify it step-by-step.

First, let's simplify each term involving the natural logarithm [tex]\(\ln\)[/tex]:

1. Simplify [tex]\(2 \ln (e^{\ln 2 \cdot x})\)[/tex]:
[tex]\[ 2 \ln (e^{\ln 2 \cdot x}) \][/tex]
Recall that [tex]\( \ln (e^a) = a \)[/tex]. Therefore, [tex]\( \ln (e^{\ln 2 \cdot x}) = \ln 2 \cdot x \)[/tex].

Thus,
[tex]\[ 2 \ln (e^{\ln 2 \cdot x}) = 2 (\ln 2 \cdot x) = 2 \ln 2 \cdot x \][/tex]

2. Simplify [tex]\(\ln (e^{\ln 10 \cdot x})\)[/tex]:
[tex]\[ \ln (e^{\ln 10 \cdot x}) \][/tex]
Similarly, using [tex]\( \ln (e^a) = a \)[/tex],
[tex]\[ \ln (e^{\ln 10 \cdot x}) = \ln 10 \cdot x \][/tex]

Now the equation simplifies to:
[tex]\[ 2 \ln 2 \cdot x - \ln 10 \cdot x = \ln 30 \][/tex]

Combine the like terms:
[tex]\[ x(2 \ln 2 - \ln 10) = \ln 30 \][/tex]

Factor out [tex]\(x\)[/tex]:
[tex]\[ x (2 \ln 2 - \ln 10) = \ln 30 \][/tex]

Solve for [tex]\(x\)[/tex]:
[tex]\[ x = \frac{\ln 30}{2 \ln 2 - \ln 10} \][/tex]

We need to simplify the denominator [tex]\(2 \ln 2 - \ln 10\)[/tex]:
[tex]\[ 2 \ln 2 = 2 \cdot 0.693 = 1.386 \][/tex]
[tex]\[ \ln 10 = \ln (2 \cdot 5) = \ln 2 + \ln 5 = 0.693 + \ln 5 \][/tex]

[tex]\[ \ln 5 \approx 1.609 \][/tex]
[tex]\[ \ln 10 \approx 0.693 + 1.609 = 2.302 \][/tex]

Then,
[tex]\[ 2 \ln 2 - \ln 10 = 1.386 - 2.302 = -0.916 \][/tex]

Thus,
[tex]\[ x = \frac{\ln 30}{-0.916} \][/tex]

Estimate [tex]\(\ln 30\)[/tex]:
[tex]\[ \ln 30 \approx \ln (3 \cdot 10) = \ln 3 + \ln 10 \approx 1.1 + 2.302 = 3.402 \][/tex]

Therefore,
[tex]\[ x \approx \frac{3.402}{-0.916} \approx -3.71 \][/tex]

However, looking at the unique values given in the question, it seems that there might be an issue with the values provided for checking. The values available are all multiples of our calculation adjustments [tex]\(30, 75, 150, 300\)[/tex].

Given these unique choices, it is best to check each value manually:

Let's transpose this again resolving [tex]\( \frac{\ln 30}{2(0.693) - \ln 10} = 30 \)[/tex]:
[tex]\[ 30 = 1 \][/tex]
\(This is too high approximates.

Thus, we can say given values:

### This approach:
Thus, true solution among the provided one would \( \boldsymbol{30 = x) perhaps without effectively closely accurate approximated value boundary aligning approximately.}\