Đáp án: A= √[3](200+80√(5) ) =a + b √5 Tìm a-b - Đáp án a-b=4 Giải thích các bước giải A=[3](200+80√(5)) A=[3](125+75√(5)+5√(5)+75) A=[3](5^3+35^(2)√(5)+3(√(5))^2+(√(5))^3) A=[3]((5+√(5))^3) A=5+√(5) Mà A=[3](200+80√(5))=a+b√(5) =>a=5;b=1 =>a-b=5-1=4 Vậy a-b=4

Đáp án a-b=4 Giải thích các bước giải A=[3](200+80√(5)) A=[3](125+75√(5)+5√(5)+75) A=[3](5^3+35^(2)√(5)+3(√(5))^2+(√(5))^3) A=[3]((5+√(5))^3) A=5+√(5) Mà A=[3](200+80√(5))=a+b√(5) =>a=5;b=1 =>a-b=5-1=4 Vậy a-b=4

ngocksks

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A= $\sqrt[3]{200+80\sqrt[]{5} }$ =a + b √5. Tìm a-b

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chinhphuctatca

6 tháng trước

Đáp án:

`a-b=4`

Giải thích các bước giải:

`A=\root[3]{200+80\sqrt{5}}`

`A=\root[3]{125+75\sqrt{5}+5\sqrt{5}+75}`

`A=\root[3]{5^3+3.5^{2}.\sqrt{5}+3.(\sqrt{5})^2+(\sqrt{5})^3}`

`A=\root[3]{(5+\sqrt{5})^3}`

`A=5+\sqrt{5}`

Mà `A=\root[3]{200+80\sqrt{5}}=a+b\sqrt{5}`

`=>a=5;b=1`

`=>a-b=5-1=4`

Vậy `a-b=4`

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Choose the best answer.
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I think that ______ cauliflower is not enough for 3 people. Let’s buy one more.

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A= $\sqrt[3]{200+80\sqrt[]{5} }$ =a + b √5. Tìm a-b

1 câu trả lời

Viết một đoạn văn hoàn chỉnh về lý do học tiếng Anh bằng cách đưa ra các manh mối ( ko chép mạng nhá)

việt nam dành độc lập vào năm nào

Choose the best answer.I think you should buy _____ pack of mineral water instead. And you can also buy _____ snacks such as potato crisps, 3 kilos of mandarins, 2 kilos of apples, 3 bunches of bananas, ______ cookies and soft candies.

Choose the best answer.We should decorate our living room with _____ orange banner. We also need ________ ribbons, balloons, party hats and costume.

Choose the best answer.I think that ______ cauliflower is not enough for 3 people. Let’s buy one more.

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Choose the best answer.
I think you should buy ___ pack of mineral water instead. And you can also buy _ snacks such as potato crisps, 3 kilos of mandarins, 2 kilos of apples, 3 bunches of bananas, ____ cookies and soft candies.

Choose the best answer.
We should decorate our living room with _ orange banner. We also need ____ ribbons, balloons, party hats and costume.

Choose the best answer.
I think that ______ cauliflower is not enough for 3 people. Let’s buy one more.