Đáp án: -sqrt(-x^2+2x-1)xác định khi nào? - (√(- x² + 2x - 1) xác định) (⇔ - x² + 2x - 1 ≥ 0) (⇔ - (x² - 2x + 1) ≥ 0) (⇔ - (x - 1)² ≥ 0) (⇔ (x - 1)² ≤ 0) (Mà (x - 1)² ≥ 0 với ∀ x) (⇒ x - 1 = 0) (⇔ x = 1) (Vậy √(- x² + 2x - 1) xác định khi x = 1) (Ha1zzz)

(√(- x² + 2x - 1) xác định) (⇔ - x² + 2x - 1 ≥ 0) (⇔ - (x² - 2x + 1) ≥ 0) (⇔ - (x - 1)² ≥ 0) (⇔ (x - 1)² ≤ 0) (Mà (x - 1)² ≥ 0 với ∀ x) (⇒ x - 1 = 0) (⇔ x = 1) (Vậy √(- x² + 2x - 1) xác định khi x = 1) (Ha1zzz)

Dieulinhcute178

4 tháng trước

`-sqrt{-x^2+2x-1}`xác định khi nào?

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Ha1zzz

4 tháng trước

$\text{$\sqrt{- x² + 2x - 1}$ xác định}$

$\text{⇔ - x² + 2x - 1 ≥ 0}$

$\text{⇔ - (x² - 2x + 1) ≥ 0}$

$\text{⇔ - (x - 1)² ≥ 0}$

$\text{⇔ (x - 1)² ≤ 0}$

$\text{Mà (x - 1)² ≥ 0 với ∀ x}$

$\text{⇒ x - 1 = 0}$

$\text{⇔ x = 1}$

$\text{Vậy $\sqrt{- x² + 2x - 1}$ xác định khi x = 1}$

$\textit{Ha1zzz}$

dungsenpai247

4 tháng trước

`-`$\sqrt{-x² + 2x - 1}$

` = -`$\sqrt{-( x² - 2x + 1 )}$

` = -`$\sqrt{ -( x - 1 )² }$

Do biểu thức có chứa ẩn dưới mẫu nên để biểu thức xác định thì :

` - ( x - 1 )² ≥0 `

` ⇔ ( x - 1 )² ≤ 0 `

mà ` ( x - 1 )² ≥ 0 ∀ x ∈ Z `

` ⇒ x - 1 = 0 `

` ⇔ x = 1 `

Vậy điều kiện xác định của bài là ` x = 1 `

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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.

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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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`-sqrt{-x^2+2x-1}`xác định khi nào?

2 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.

Đề thi - đề kiểm tra Xem thêm

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.