Changing the base of logarithms

Suppose log_dx = l and we want to convert to base b.

Then d^l=x

Let log_bd = q so b^q=d

Substituting for d, (b^q)^l = x = b^ql

So log_bx = ql

You can think of this in a couple of ways, which should be memorable. -mathformula not MarkupType-
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