We use the log law:

log ab = log a + log b

We can write our question as:

y = ln 2x = ln 2 + ln x

Now, the derivative of a constant is 0, so

`d/(dx)ln\ 2=0`

So we are left with (from our formula above)

`d/(dx)(ln\ x)=1/x`

The final answer is:

`(dy)/(dx)=1/x`

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