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E=$(2+1)(2^2+1)(2^4+1)(2^8+1)$

Nguyễn Thanh Hằng · Accepted Answer

Ta có :

$E=\left(2+1\right)\left(2^2+1\right)\left(2^4+1\right)\left(2^8+1\right)$

$\Leftrightarrow2E=\left(2-1\right)\left(2+1\right)\left(2^2+1\right)\left(2^4+1\right)\left(2^8+1\right)$

$\Leftrightarrow2E=\left(2^2-1\right)\left(2^2+1\right)\left(2^4+1\right)\left(2^8+1\right)$

$\Leftrightarrow2E=\left(2^4-1\right)\left(2^4+1\right)\left(2^8+1\right)$

$\Leftrightarrow2E=\left(2^8-1\right)\left(2^8+1\right)$

$\Leftrightarrow2E=2^{16}-1$

$\Leftrightarrow E=\dfrac{2^{16}-1}{2}$Câu trả lời: Ta có :

$E=\left(2+1\right)\left(2^2+1\right)\left(2^4+1\right)\left(2^8+1\right)$

$\Leftrightarrow2E=\left(2-1\right)\left(2+1\right)\left(2^2+1\right)\left(2^4+1\right)\left(2^8+1\right)$

$\Leftrightarrow2E=\left(2^2-1\right)\left(2^2+1\right)\left(2^4+1\right)\left(2^8+1\right)$

$\Leftrightarrow2E=\left(2^4-1\right)\left(2^4+1\right)\left(2^8+1\right)$

$\Leftrightarrow2E=\left(2^8-1\right)\left(2^8+1\right)$

$\Leftrightarrow2E=2^{16}-1$

$\Leftrightarrow E=\dfrac{2^{16}-1}{2}$

Trần Minh Anh · Answer

$E=\left(2+1\right)\left(2^2+1\right)\left(2^4+1\right)\left(2^8+1\right)$

$E=\left(2-1\right)\left(2+1\right)\left(2^2+1\right)\left(2^4+1\right)\left(2^8+1\right)$

$E=\left(2^2-1\right)\left(2^2+1\right)\left(2^4+1\right)\left(2^8+1\right)$

$E=\left(2^4-1\right)\left(2^4+1\right)\left(2^8+1\right)$

$E=\left(2^8-1\right)\left(2^8+1\right)=2^{16}-1$Câu trả lời: $E=\left(2+1\right)\left(2^2+1\right)\left(2^4+1\right)\left(2^8+1\right)$

$E=\left(2-1\right)\left(2+1\right)\left(2^2+1\right)\left(2^4+1\right)\left(2^8+1\right)$

$E=\left(2^2-1\right)\left(2^2+1\right)\left(2^4+1\right)\left(2^8+1\right)$

$E=\left(2^4-1\right)\left(2^4+1\right)\left(2^8+1\right)$

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

Bài 4: Những hằng đẳng thức đáng nhớ (Tiếp)