Đáp án: Giai phương trình vô tỷ √(4x² - 7x - 2 ) = 2 √(x² - x + 1) - Giải thích các bước giải √(4x^2 -7x-2)=2√(x^2 -x+1) (ĐK AAx) <=>√(4x^2 -7x-2)^2=(2√(x^2 -x+1))^2 <=>4x^2 -7x-2=4(x^2 -x+1) <=>4x^2 -7x-2=4x^2 -4x+4 <=>4x^2 -7x-4x^2 +4x=4+2 <=>-3x=6 <=>x=-2(tmđk) (Vậy phương trình có tập nghiệm)S=(-2)

Giải thích các bước giải √(4x^2 -7x-2)=2√(x^2 -x+1) (ĐK AAx) <=>√(4x^2 -7x-2)^2=(2√(x^2 -x+1))^2 <=>4x^2 -7x-2=4(x^2 -x+1) <=>4x^2 -7x-2=4x^2 -4x+4 <=>4x^2 -7x-4x^2 +4x=4+2 <=>-3x=6 <=>x=-2(tmđk) (Vậy phương trình có tập nghiệm)S=(-2)

pnl123456789

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Giai phương trình vô tỷ : √(4x² - 7x - 2 ) = 2 . √(x² - x + 1)

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Avi Anh

5 tháng trước

Giải thích các bước giải:

`\sqrt{4x^2 -7x-2}=2\sqrt{x^2 -x+1}` `(ĐK: AAx)`

`<=>\sqrt{4x^2 -7x-2}^2=(2\sqrt{x^2 -x+1})^2`

`<=>4x^2 -7x-2=4(x^2 -x+1)`

`<=>4x^2 -7x-2=4x^2 -4x+4`

`<=>4x^2 -7x-4x^2 +4x=4+2`

`<=>-3x=6`

`<=>x=-2(tmđk)`

`\text{Vậy phương trình có tập nghiệm:}``S={-2}`

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Giai phương trình vô tỷ : √(4x² - 7x - 2 ) = 2 . √(x² - x + 1)

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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.