Đáp án: Cho hàm số y=fx=(x^3+6x-5)^2015 Tính f(a) với a= ³ √(3+ √17) + ³ √(3- √17) - Đáp án 1 Giải thích các bước giải a=√[3](3+√(17))+√[3](3-√(17)) a^3=(√[3](3+√(17))+√[3](3-√(17)))^3 =√[3](3+√(17))^3+√[3](3-√(17))^3+3√[3](3+√(17))√[3](3-√(17))(√[3](3+√(17))+√[3](3-√(17))) =3+√(17)+3-√(17)+3√[3]((3+√(17))(3-√(17)))a =6+3√[3](9-17)a =6+3√[3](-8)a =6-6a ⇒ a^3=6-6a ⇔ a^3+6a-6=0 ⇔ a^3+...

Đáp án 1 Giải thích các bước giải a=√[3](3+√(17))+√[3](3-√(17)) a^3=(√[3](3+√(17))+√[3](3-√(17)))^3 =√[3](3+√(17))^3+√[3](3-√(17))^3+3√[3](3+√(17))√[3](3-√(17))(√[3](3+√(17))+√[3](3-√(17))) =3+√(17)+3-√(17)+3√[3]((3+√(17))(3-√(17)))a =6+3√[3](9-17)a =6+3√[3](-8)a =6-6a ⇒ a^3=6-6a ⇔ a^3+6a-6=0 ⇔ a^3+...

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Cho hàm số `y=f(x)=(x^3+6x-5)^2015` `.` Tính `f(a)` với `a=` ³ √(3+ √17) + ³ √(3- √17)

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hoang1o1o1

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Đáp án:

$1.$

Giải thích các bước giải:

$a=\sqrt[3]{3+\sqrt{17}}+\sqrt[3]{3-\sqrt{17}}\\ a^3=\left(\sqrt[3]{3+\sqrt{17}}+\sqrt[3]{3-\sqrt{17}}\right)^3\\ =\sqrt[3]{3+\sqrt{17}}^3+\sqrt[3]{3-\sqrt{17}}^3+3\sqrt[3]{3+\sqrt{17}}.\sqrt[3]{3-\sqrt{17}}\left(\sqrt[3]{3+\sqrt{17}}+\sqrt[3]{3-\sqrt{17}}\right)\\ =3+\sqrt{17}+3-\sqrt{17}+3\sqrt[3]{(3+\sqrt{17})(3-\sqrt{17})}a\\ =6+3\sqrt[3]{9-17}a\\ =6+3\sqrt[3]{-8}a\\ =6-6a\\ \Rightarrow a^3=6-6a\\ \Leftrightarrow a^3+6a-6=0\\ \Leftrightarrow a^3+6a-5=1\\ f(a)=(a^3+6a-5)^{2015}=1^{2015}=1.$

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Cho hàm số `y=f(x)=(x^3+6x-5)^2015` `.` Tính `f(a)` với `a=` ³ √(3+ √17) + ³ √(3- √17)

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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.

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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Cho hàm số `y=f(x)=(x^3+6x-5)^2015` `.` Tính `f(a)` với `a=` ³ √(3+ √17) + ³ √(3- √17)

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.

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.