Solve ln (3+x)=7: Get x=1093.63

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To solve the equation ln(3+x)=7, the correct approach leads to the expression 3+x=e^7, resulting in x=e^7-3. The calculated value of x is approximately 1093.63, which is an approximation rather than the exact answer. It is suggested to present the solution as x=e^7-3 for clarity and precision. The method used to arrive at the solution is valid, but emphasizing the exact form is recommended.
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Hello,
Am trying to solve this natural log problem, where i have to find the value of x.

ln (3+x)=7

this is what i have done

3+x= e7
x= 1093.63

This is the answer am getting, but its wrong. Can someone please let me know what am doing wrong, thanks.
 
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Well the answer isn't 'wrong', but it's only an approximation, why not leave it as an exact answer? It seems that your method was ok...

\ln \left( {3 + x} \right) = 7 \Leftrightarrow 3 + x = e^7 \Leftrightarrow x = e^7 - 3 \Leftrightarrow x \approx 1093.633158 \ldots

So instead of doing that last stap (see how I didn't the equality sign?) just leave it as x = e^7 - 3.
 
TD said:
Well the answer isn't 'wrong', but it's only an approximation, why not leave it as an exact answer? It seems that your method was ok...

\ln \left( {3 + x} \right) = 7 \Leftrightarrow 3 + x = e^7 \Leftrightarrow x = e^7 - 3 \Leftrightarrow x \approx 1093.633158 \ldots

So instead of doing that last stap (see how I didn't the equality sign?) just leave it as x = e^7 - 3.

Thanks for ur help.
 
You're welcome :smile:
 
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