We use the log law:

log

ab= loga+ logb

We can write our question as:

y= ln 2x= ln 2 + lnx

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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