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Solve for x:
log(x + 4) -log(x + 1) = 2

User Sharun
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1 Answer

3 votes

The solution to the logarithmic equation
\( \log(x + 4) - \log(x + 1) = 2 \) is
\( x = -(32)/(33) \).

To solve the logarithmic equation
\( \log(x + 4) - \log(x + 1) = 2 \), you can use logarithmic properties.

Recall the property
\( \log(a) - \log(b) = \log\left((a)/(b)\right) \). Apply this property to the given equation:
\[ \log(x + 4) - \log(x + 1) = \log\left((x + 4)/(x + 1)\right) \]

Now, the equation becomes:
\[ \log\left((x + 4)/(x + 1)\right) = 2 \]

To eliminate the logarithm, you can rewrite the equation in exponential form. Since the base of the logarithm is 10 (common logarithm), you can rewrite it as:
\[ 10^2 = (x + 4)/(x + 1) \]

Now, solve for x:
\[ 100 = (x + 4)/(x + 1) \]

Multiply both sides b (x + 1) to get rid of the fraction: 100(x + 1) = x + 4

Distribute on the left side: 100x + 100 = x + 4

Subtract x from both sides: 99x + 100 = 4

Subtract 100 from both sides: 99x = -96

Divide by 99 to solve for x:
\[ x = -(96)/(99) \]

Simplify the fraction:
\[ x = -(32)/(33) \]

So, the solution to the equation is
\( x = -(32)/(33) \).

User Comencau
by
7.7k points