Question

\(A=2^7+2^8+2^9+2^{10}+.....+2^{34}\)

Nhanh nha!Mk cần lời giải nha! Thank you

Answer 1

\(A=2^7+2^8+2^9+2^{10}+...+2^{34}\)

\(\Rightarrow2A=2\left(2^7+2^8+2^9+2^{10}+...+2^{34}\right)\)

\(\Rightarrow2A=2^8+2^9+2^{10}+...+2^{35}\)

\(\Rightarrow2A-A=\left(2^8+2^9+2^{10}+...+2^{35}\right)-\left(2^7+2^8+2^9+2^{10}+...+2^{34}\right)\)

\(\Rightarrow A=2^{35}-2^7\)

Answer 2

\(A=2^7+2^8+2^9+2^{10}+...+2^{34}\\ 2A=2^8+2^9+2^{10}+2^{11}+...+2^{35}\\ 2A-A=\left(2^8+2^9+2^{10}+2^{11}+...+2^{35}\right)-\left(2^7+2^8+2^9+2^{10}+...+2^{34}\right)\\ A=2^{35}-2^7\)