#1375 · Algebra · Sequences & series

Sum of powers of two

Prove by induction that $2 + 2^{2} + 2^{3} + oo + 2^{n} = 2 (2^{n} - 1)$ for all positive integers $n$ .

~10 minProof · checked by AImathematical inductiongeometric progression

H. S. Hall & S. R. Knight, Higher Algebra (1891) · Ch. XII. Mathematical Induction, Examples XII, No. 3

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