Question

Bài tập: So sánh:

A= (2 +1) (2² +1) (2⁴ +1)(2⁸+1) (2¹⁶+1) và B = 2³² -1

Giúp mik với ạ !!!

Answer 1

Ta có :

\(A=\left(2+1\right)\left(2^2+1\right)\left(2^4+1\right)\left(2^8+1\right)\left(2^{16}+1\right)\)

\(=\left(2^2-1\right)\left(2^2+1\right)\left(2^4+1\right)\left(2^8+1\right)\left(2^{16}+1\right)\)

\(=\left(2^4-1\right)\left(2^4+1\right)\left(2^8+1\right)\left(2^{16}+1\right)\)

\(=\left(2^8-1\right)\left(2^8+1\right)\left(2^{16}+1\right)\)

\(=\left(2^{16}-1\right)\left(2^{16}+1\right)\)

\(=2^{32}-1\)

Vậy \(A=B\)

Chúc bạn học tốt !