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I've using Google search engine graphing tool for a while, but now I'm trying to plot a logarithm function like :$\log_2(x + 1) + 2$

How to pass this notation for the graphing tool ? Thanks

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Use the change of base formula:

$$ \log_b(a)=\frac{\log_c(a)}{\log_c(b)} $$

So for you example, you would do:

$$ \frac{\ln(x+1)}{\ln(2)}+2 $$

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Just Google for lg(x+1) + 2. Here “lg” is the standard notation in computer science for a base-two logarithm.

If you didn’t know that, you could have got the same graph by typing log(x+1)/log(2) + 2, making use of the fact that $\log_k(x) = \log_n(x)/\log_n(k)$ for any base $n$.

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