Question

[Bùi Minh Ngọc]

2^2+2^2+2^3+2^4+.......+2^2013=2^x

Answer 1

[Akai Haruma]

Lời giải:

Đặt $A=2^2+2^2+2^3+2^4+...+2^{2013}$

$2A=2^3+2^3+2^4+2^5+...+2^{2014}$

$\Rightarrow A=2A-A=(2^3+2^3+2^4+2^5+...+2^{2014})-(2^2+2^2+2^3+2^4+...+2^{2013})$

$\Rightarrow A=(2^3+2^{2014})-(2^2+2^2)=2^{2014}$

Vậy $A=2^{2014}=2^x$

$\Rightarrow x=2014$

Answer 2

[Phan Hoang Minh]

x=2014