Đáp án: tính D=(5+√(5))/(√(5)+2)+(√(5)-5)/(√(5))-11/(2√(5)+3) - D=

Đáp án + Giải thích các bước giải D=(5+√5)/(√5+2)+(√5-5)/(√5)-11/(2√5+3) =>D=((5+√5)(√5-2))/((√5+2)(√5-2))+(√5(1-√5))/(√5)-(20-9)/(2√5+3) =>D=(5(√5-2)+√5(√5-2))/((√5)^2-2^2)+1-√5-((2√5)^2-3^2)/(2√5+3) =>D=(5√5-10+5-2√5)/(5-4)+1-√5-((2√5-3)(2√5+3))/(2√5+3) =>D=3√5-5+1-√5-(2√5-3) =>D=2√5-4-2√5+3 =>D=-1 Vậy D=-1

GraceChiWa

6 tháng trước

tính $D=(5+\sqrt{5})/(\sqrt{5}+2)+(\sqrt{5}-5)/(\sqrt{5})-11/(2\sqrt{5}+3)$

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Nguyễn Phúc

6 tháng trước

miku247

6 tháng trước

Đáp án + Giải thích các bước giải:

$D=(5+\sqrt5)/(\sqrt5+2)+(\sqrt5-5)/(\sqrt5)-11/(2\sqrt5+3)$

$=>D=((5+\sqrt5)(\sqrt5-2))/((\sqrt5+2)(\sqrt5-2))+(\sqrt5(1-\sqrt5))/(\sqrt5)-(20-9)/(2\sqrt5+3)$

$=>D=(5(\sqrt5-2)+\sqrt5(\sqrt5-2))/((\sqrt5)^2-2^2)+1-\sqrt5-((2\sqrt5)^2-3^2)/(2\sqrt5+3)$

$=>D=(5\sqrt5-10+5-2\sqrt5)/(5-4)+1-\sqrt5-((2\sqrt5-3)(2\sqrt5+3))/(2\sqrt5+3)$

$=>D=3\sqrt5-5+1-\sqrt5-(2\sqrt5-3)$

$=>D=2\sqrt5-4-2\sqrt5+3$

$=>D=-1$

Vậy $D=-1$

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tính $D=(5+\sqrt{5})/(\sqrt{5}+2)+(\sqrt{5}-5)/(\sqrt{5})-11/(2\sqrt{5}+3)$

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