Đáp án: giải pt √(2x^2+10x+8)+√(x^2-1)=2x+2 - Đáp án + Giải thích Dòng số 3 mik có ghi đậm bút là số 4 bạn nhé

√(2(x^2+5x+4))+√(x^2-1)=2x+2 ⇔√(2x^2+10x+8)+√(x^2-1)=2x+2 ⇔√(2(x+1)(x+4))+√((x+1)(x-1))=2x+2 ⇔2x^2+10x+8+(2x+2)⋅ 2(x+4)(x-1)+(x+1)(x-1)=4x^2+8x+4 ⇔4x^3+19x^2+6x-9=4x^2+8x+4 ⇔4x^3+15x^2-2x-13=0 ⇔[ (l)x+1=0 4x^2+11x-13=0 ⇔[ (l)x=-1(tm)x=(-11+√(329)/8), x=(-11-√(329)/8)(ktm) (Vậy pt có nghiệm S = (-1))

hhhhhtttt

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giải pt $\sqrt{2x^2+10x+8}+\sqrt{x^2-1}=2x+2$

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Huyen Kim

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Đáp án + Giải thích Dòng số 3 mik có ghi đậm bút là số 4 bạn nhé

baonhivu1234

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$\sqrt{2\left(x^2+5x+4\right)}+\sqrt{x^2-1}=2x+2$

$⇔\sqrt{2x^2+10x+8}+\sqrt{x^2-1}=2x+2$

$⇔\sqrt{2\left(x+1\right)\left(x+4\right)}+\sqrt{\left(x+1\right)\left(x-1\right)}=2x+2$

$⇔2x^2+10x+8+\left(2x+2\right)\cdot \:2\left(x+4\right)\left(x-1\right)+\left(x+1\right)\left(x-1\right)=4x^2+8x+4$

$⇔4x^3+19x^2+6x-9=4x^2+8x+4$

$⇔4x^3+15x^2-2x-13=0$

$⇔\left[ \begin{array}{l}x+1=0\\\:4x^2+11x-13=0\end{array} \right.$ $⇔\left[ \begin{array}{l}x=-1(tm)\\x=\dfrac{-11+\sqrt{329}}{8},\:x=\dfrac{-11-\sqrt{329}}{8}(ktm)\end{array} \right.$

$\text{Vậy pt có nghiệm S = {-1}}$

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giải pt $\sqrt{2x^2+10x+8}+\sqrt{x^2-1}=2x+2$

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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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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.

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