Question

Tính A=1+2+2²+2³+....+2²⁰²⁴

Answer 1

\(A=1+2+2^2+2^3+...+2^{2024}\)

=>\(2A=2+2^2+2^3+...+2^{2025}\)

=>\(2A-A=2+2^2+2^3+...+2^{2025}-1-2-...-2^{2024}\)

=>\(A=2^{2025}-1\)

Answer 2

A=1+2+22+23+...+22024�=1+2+22+23+...+22024

=>2A=2+22+23+...+220252�=2+22+23+...+22025

=>2A−A=2+22+23+...+22025−1−2−...−220242�−�=2+22+23+...+22025−1−2−...−22024

=>A=22025−1