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mong mn giúp mik, mình cần gấp

Lấp La Lấp Lánh · Accepted Answer

$\dfrac{4^{13}}{4^{13}-2}=1+\dfrac{2}{4^{13}-2}$

$\dfrac{4^{13}-1}{4^{13}+1}=1-\dfrac{2}{4^{13}+1}$

Do $4^{13}-2< 4^{13}+1\Rightarrow\dfrac{2}{4^{13}-2}>\dfrac{2}{4^{13}+1}\Rightarrow\dfrac{2}{4^{13}-2}>-\dfrac{2}{4^{13}-1}$

$\Rightarrow\dfrac{4^{13}}{4^{13}-2}>\dfrac{4^{13}-1}{4^{13}+1}$

Câu trả lời:

$\dfrac{4^{13}}{4^{13}-2}=1+\dfrac{2}{4^{13}-2}$

$\dfrac{4^{13}-1}{4^{13}+1}=1-\dfrac{2}{4^{13}+1}$

Do $4^{13}-2< 4^{13}+1\Rightarrow\dfrac{2}{4^{13}-2}>\dfrac{2}{4^{13}+1}\Rightarrow\dfrac{2}{4^{13}-2}>-\dfrac{2}{4^{13}-1}$

$\Rightarrow\dfrac{4^{13}}{4^{13}-2}>\dfrac{4^{13}-1}{4^{13}+1}$

Minh Hiếu · Answer

Ta có:

$\dfrac{4^{13}}{4^{13}-2}=\dfrac{4^{13}-2}{4^{13}-2}+\dfrac{2}{4^{13}-2}=1+\dfrac{2}{4^{13}-2}$

$\dfrac{4^{13}-1}{4^{13}+1}=\dfrac{4^{13}+1}{4^{13}+1}-\dfrac{2}{4^{13}+1}=1-\dfrac{2}{4^{13}+1}$

Vì $1+\dfrac{2}{4^{13}-2}>1-\dfrac{2}{4^{13}+1}$

⇒$\dfrac{4^{13}}{4^{13}-2}>$$\dfrac{4^{13}-1}{4^{13}+1}$