Rút gọn các biểu thức sau: B = 3.( 2^2 + 1 )( 2^4 + 1).....(2^64 + 1) +1

* Hướng dẫn giải

$\begin{array}{l}\mathrm{B}=3.\left(2^2+1\right)\left(2^4+1\right)\mathrm{.....}\left(2^{64}+1\right)+1\\ =\left(2^2-1\right)\left(2^2+1\right)\left(2^4+1\right)\mathrm{.....}\left(2^{64}+1\right)+1\\ =\left(2^4-1\right)\left(2^4+1\right)\mathrm{.....}\left(2^{64}+1\right)+1\\ =\mathrm{.....}\\ =2^{128}-1+1=2^{128}\end{array}$