Hello!
I think your equation is
`3^(2x-1)=5^x,`
not
`3^(2x)-1=5^x.`
For the first option yes, apply `ln` to both sides (they are both positive). It is known (and not hard) that `ln(a^b)=b*ln(a).`
Here we obtain `(2x-1)*ln(3)=x*ln(5).`
It is a linear equation for x, group like terms:
`x*(2ln(3)-ln(5))=ln(3),` so
`x=(ln(3))/(2ln(3)-ln(5)) approx 1.869.`
This is the answer for the first option.
I believe the second option cannot be solved exactly, although it has exactly one root and it is in (0, 1).
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