Đáp án: tìm giá trị của a a-2 căn a-3=0 - a - 2√(a) -3 = 0 ( ĐK a ≥ 0 ) ⇔ ( √(a) )² - 2√(a) -3 = 0 ⇔ ( √(a) )² + √(a) - 3√(a) -3 = 0 ⇔ √(a) ( √(a) + 1 ) - 3 ( √(a) + 1 ) = 0 ⇔ ( √(a) - 3 ) ( √(a) + 1 ) = 0 Do √(a) + 1 > 0 ∀ a ∈ Z nên để đa thức bằng 0 thì √(a) - 3 = 0 ⇔ √(a) = 3 ⇔ a = 9 Vậy a = 9

a - 2√(a) -3 = 0 ( ĐK a ≥ 0 ) ⇔ ( √(a) )² - 2√(a) -3 = 0 ⇔ ( √(a) )² + √(a) - 3√(a) -3 = 0 ⇔ √(a) ( √(a) + 1 ) - 3 ( √(a) + 1 ) = 0 ⇔ ( √(a) - 3 ) ( √(a) + 1 ) = 0 Do √(a) + 1 > 0 ∀ a ∈ Z nên để đa thức bằng 0 thì √(a) - 3 = 0 ⇔ √(a) = 3 ⇔ a = 9 Vậy a = 9

thip9062

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tìm giá trị của a a-2 căn a-3=0

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dungsenpai247

3 tháng trước

` a - 2`$\sqrt{a}$ `-3 = 0 ` ( ĐK ` a ≥ 0 ` )

` ⇔ ( ` $\sqrt{a}$ ` )² - 2`$\sqrt{a}$ `-3 = 0 `

` ⇔ ( ` $\sqrt{a}$ ` )² + ` $\sqrt{a}$ ` - 3`$\sqrt{a}$ `-3 = 0 `

` ⇔ ` $\sqrt{a}$ ( $\sqrt{a}$ ` + 1 ` ) ` - 3 ` ( $\sqrt{a}$ ` + 1 ) = 0 `

` ⇔ ` ( $\sqrt{a}$ ` - 3 ` ) ( $\sqrt{a}$ ` + 1 ` ) ` = 0 `

Do $\sqrt{a}$ ` + 1 > 0 ∀ a ∈ Z ` nên để đa thức bằng ` 0 ` thì :

$\sqrt{a}$ ` - 3 = 0 `

` ⇔ ` $\sqrt{a}$ ` = 3 `

` ⇔ a = 9 `

Vậy ` a = 9 `

Karen1234

3 tháng trước

Đáp án:

a=3

Giải thích các bước giải:

a-2 căn a-3=0

<=> căn a-3=0

<=>a-3=0

<=>a=3

#vote cho t nha

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tìm giá trị của a a-2 căn a-3=0

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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.

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

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