Question

2^x-1=128

Answer 1

\[2^x-1=128\]
Add 1 to both sides.\[2^x-1=128\]\[~~~+1~~~~+1\]\[2^x=129\]take log of both sides,\[\log(2^{x})=\log(129)\]simplify the log...
\[x~\log(2)=\log(129)\]THEN....\[x~\log(2)~\div \log(2)=\log(129)~\div~\log(2)\]\[x=\log(129)~\div~\log(2)\]\[x=\log_2(129)\]

Answer 2

if it is \[2^{x-1}=128\]
\[128=2^? \]