Proof

Answer all the questions below and press submit to see how many you got right.

id: 20836

We want to proof by induction that $\frac{1}{2}+\frac{1}{4}+\ldots+\frac{1}{2^n}=\frac{2^n-1}{2^n}$ for all $n\geq 1.$ What could be the basis for the induction?

  • $\frac{1}{2}+\frac{1}{4}+\ldots+\frac{1}{2^n}=\frac{2^n-1}{2^n}$
    $\frac{1}{2}+\frac{1}{3}=\frac{5}{6}$
    $\frac{1}{2}=\frac{2^1-1}{2^1}$
    $\frac{1}{2}+\frac{1}{4}+\ldots+\frac{1}{2^{n-1}}=\frac{2^{n-1}-1}{2^{n-1}}$