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Someone who’s good at logs please help lol

Someone who’s good at logs please help lol-example-1
User Freshr
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1 Answer

3 votes

To three significant figures, the value of 3 log47 is approximately 7.984. The solution to the equation
\(\log_3{x} = (1)/(log_27(x))\) is
\(x = 3√(3)\).

To convert 3 log47 to base e, we can use the change of base formula:

loga(x) = logb(x) / logb(a)

In this case, a = 47, b = e, and x = 3. So, we have:

3 log47 = 3 loge(474) / loge(10)

Using a calculator, we can find that loge(474) ≈ 6.160, and loge(10) ≈ 2.303. Plugging these values into the equation, we get:

3 log47 ≈ 3 * 6.160 / 2.303 ≈ 7.984

So, to three significant figures, the value of 3 log47 is approximately 7.984.

For the second question:

To solve the equation
\(\log_3{x} = (1)/(log_27(x))\), let's first simplify the expression on the right side.

Recall that
\(log_a^n(b) = (1)/(n) \log_a{b}\). Applying this property to
\(log_27(x)\), we get:


\((1)/(log_27(x)) = \frac{1}{(1)/(3)\log_3{x}}\).

Now, let's substitute this into the original equation:


\(\log_3{x} = \frac{1}{(1)/(3)\log_3{x}}\).

To get rid of the fraction in the denominator, multiply both sides by
\((1)/(3)\log_3{x}\):


\((1)/(3)\log_3{x} \cdot \log_3{x} = 1\).

Now, solve for
\(\log_3{x}\):


\(\log_3{x} \cdot (1)/(3)\log_3{x} = 1\).

Multiply both sides by 3:


\(\log_3{x} \cdot \log_3{x} = 3\).

Simplify the left side:


\(\log_3{x^2} = 3\).

Now, exponentiate both sides:


\(x^2 = 3^3\).


\(x^2 = 27\).

Now, take the square root of both sides (since we're looking for a positive value of x):


\(x = √(27)\).

Simplify:


\(x = 3√(3)\).

So, the solution to the equation is
\(x = 3√(3)\).

User Willi Mentzel
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