C-04-Q099mediumsingle_mcq2n−12n−1=?\dfrac{2^n - 1}{2^{n-1}} = ?2n−12n−1=?a2−21−n2 - 2^{1-n}2−21−nb2−2−n2 - 2^{-n}2−2−nc21−n−12^{1-n} - 121−n−1d12\dfrac{1}{2}21ব্যাখ্যাSplit the fraction: 2n2n−1−12n−1=2−21−n\dfrac{2^n}{2^{n-1}}-\dfrac{1}{2^{n-1}}=2-2^{1-n}2n−12n−2n−11=2−21−n.