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Duong Tue Tam
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YangSu
16 tháng 6 2023 lúc 10:34

\(A=3\left(x+2\sqrt{x}\right)-\left(\sqrt{x}-1\right)\left(\sqrt{x}+1\right)\)

\(=3x+6\sqrt{x}-\left(x-1\right)\)

\(=3x+6\sqrt{x}-x+1\)

\(=2x+6\sqrt{x}+1\)

\(B=\left(\sqrt{x}+1\right)\left(\sqrt{x}+3\right)-2\left(\sqrt{x}-1\right)^2\)

\(=x+3\sqrt{x}+\sqrt{x}+3-2\left(x-2\sqrt{x}+1\right)\)

\(=x+4\sqrt{x}+3-2x+4\sqrt{x}-2\)

\(=-x+8\sqrt{x}+1\)

\(C=3x-3\sqrt{x}-2+\left(\sqrt{x}-1\right)\left(\sqrt{x}+1\right)\)

\(=3x-3\sqrt{x}-2+\left(\sqrt{x^2}-1\right)\)

\(=3x-3\sqrt{x}-2+x-1\)

\(=4x-3\sqrt{x}-3\)

\(D=\left(\sqrt{x}+3\right)\left(\sqrt{x}-3\right)-\left(2\sqrt{x}+1\right)\left(\sqrt{x}-2\right)\)

\(=x-9-\left(2x-3\sqrt{x}-2\right)\)

\(=x-9-2x+3\sqrt{x}+2\)

\(=-x+3\sqrt{x}-7\)

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

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

\(=x-4-2\left(2x+3\sqrt{x}-2\right)\)

\(=x-4-4x-6\sqrt{x}+4\)

\(=-3-6\sqrt{x}\)

titanic
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thu dinh
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Nguyễn Lê Phước Thịnh
3 tháng 3 2021 lúc 13:45

Ta có: \(P=\left(\dfrac{2\sqrt{x}+x+1}{\sqrt{x}+1}\right)\cdot\left(1-\dfrac{x-\sqrt{x}}{\sqrt{x}-1}\right):\left(1-\sqrt{x}\right)\)

\(=\left(\dfrac{\left(\sqrt{x}+1\right)^2}{\sqrt{x}+1}\right)\cdot\left(1-\dfrac{\sqrt{x}\left(\sqrt{x}-1\right)}{\sqrt{x}-1}\right)\cdot\dfrac{1}{1-\sqrt{x}}\)

\(=\left(\sqrt{x}+1\right)\left(1-\sqrt{x}\right)\cdot\dfrac{1}{1-\sqrt{x}}\)

\(=\sqrt{x}+1\)

Hiền Nguyễn
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do khanh hoa
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anonymous
17 tháng 12 2020 lúc 11:54

Ta có:

\(P=\left(\dfrac{x\sqrt{x}-1}{x-\sqrt{x}}-\dfrac{x\sqrt{x}+1}{x+\sqrt{x}}\right):\left[\dfrac{2\left(x-2\sqrt{x}+1\right)}{x-1}\right]\\ =\left[\dfrac{\left(\sqrt{x}-1\right)\left(x+\sqrt{x}+1\right)}{\sqrt{x}\left(\sqrt{x}-1\right)}-\dfrac{\left(\sqrt{x}+1\right)\left(x-\sqrt{x}+1\right)}{\sqrt{x}\left(\sqrt{x}+1\right)}\right]:\left[\dfrac{2\left(\sqrt{x}-1\right)^2}{\left(\sqrt{x}-1\right)\left(\sqrt{x}+1\right)}\right]\\ =2:\dfrac{2\left(\sqrt{x}-1\right)}{\sqrt{x}+1}=\dfrac{\sqrt{x}+1}{\sqrt{x}-1}\)

Miinhhoa
17 tháng 12 2020 lúc 12:05

P=\(\left(\dfrac{\sqrt{x^3}-1}{\sqrt{x}\left(\sqrt{x}-1\right)}-\dfrac{\sqrt{x^3}+1}{\sqrt{x}\left(\sqrt{x}+1\right)}\right):\left[\dfrac{2\left(\sqrt{x}-1\right)^2}{\left(\sqrt{x}-1\right)\left(\sqrt{x}+1\right)}\right]\)

P=\(\dfrac{\left(\sqrt{x}-1\right)\left(x+\sqrt{x}+1\right)}{\sqrt{x}\left(\sqrt{x}-1\right)}-\dfrac{\left(\sqrt{x}+1\right)\left(x-\sqrt{x}+1\right)}{\sqrt{x}\left(\sqrt{x}+1\right)}:\left[\dfrac{2\left(\sqrt{x}-1\right)}{\left(\sqrt{x}+1\right)}\right]\)

P=\(\dfrac{x+\sqrt{x}+1}{\sqrt{x}}-\dfrac{x-\sqrt{x}+1}{\sqrt{x}}.\dfrac{\sqrt{x}+1}{2\left(\sqrt{x}-1\right)}\)

P=\(\dfrac{x+\sqrt{x}+1-x+\sqrt{x}-1}{\sqrt{x}}.\dfrac{\sqrt{x}+1}{2\left(\sqrt{x}-1\right)}\)

P=\(\dfrac{2\sqrt{x}}{\sqrt{x}}.\dfrac{\sqrt{x}+1}{2\left(\sqrt{x}-1\right)}=\dfrac{\sqrt{x}+1}{\sqrt{x}-1}\)

Vinne
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quang
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Akai Haruma
15 tháng 4 2023 lúc 22:00

Đoạn $x\sqrt{x}-a$ là sao vậy bạn? Có nhầm lẫn gì không?

Nguyễn Lê Phước Thịnh
15 tháng 4 2023 lúc 23:19

\(=\left(\sqrt{x}+1-\dfrac{x+\sqrt{x}+1}{\sqrt{x}+1}\right):\dfrac{x-\sqrt{x}+1}{\sqrt{x}+1}\)

\(=\dfrac{x+2\sqrt{x}+1-x-\sqrt{x}-1}{\sqrt{x}+1}\cdot\dfrac{\sqrt{x}+1}{x-\sqrt{x}+1}\)

\(=\dfrac{\sqrt{x}}{x-\sqrt{x}+1}\)

Ánh Tuyết Nguyễn Thị
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Lấp La Lấp Lánh
30 tháng 8 2021 lúc 21:25

\(\left(1+\dfrac{x+\sqrt{x}}{1+\sqrt{x}}\right).\left(1+\dfrac{x-\sqrt{x}}{1-\sqrt{x}}\right)\left(đk:x\ge0,x\ne1\right)\)

\(=\dfrac{1+\sqrt{x}+x+\sqrt{x}}{1+\sqrt{x}}.\dfrac{1-\sqrt{x}+x-\sqrt{x}}{1-\sqrt{x}}\)

\(=\dfrac{\left(\sqrt{x}+1\right)^2}{\sqrt{x}+1}.\dfrac{\left(1-\sqrt{x}\right)^2}{1-\sqrt{x}}=\left(\sqrt{x}+1\right)\left(1-\sqrt{x}\right)=1-x\)

loann nguyễn
30 tháng 8 2021 lúc 21:27

\(\left(1+\dfrac{x+\sqrt{x}}{1+\sqrt{x}}\right).\left(1+\dfrac{x-\sqrt{x}}{1-\sqrt{x}}\right)\\ =\left(1+\dfrac{\sqrt{x}\left(\sqrt{x}+1\right)}{1+\sqrt{x}}\right).\left(1+\dfrac{\sqrt{x}\left(\sqrt{x}-1\right)}{1-\sqrt{x}}\right)\\ =\left(1+\sqrt{x}\right).\left(1-\sqrt{x}\right)\\ =1-x\)

Nhan Thanh
30 tháng 8 2021 lúc 21:28

\(\left(1+\dfrac{x+\sqrt{x}}{1+\sqrt{x}}\right).\left(1+\dfrac{x-\sqrt{x}}{1-\sqrt{x}}\right)\)

\(=\left(1+\dfrac{\sqrt{x}\left(\sqrt{x}+1\right)}{\sqrt{x}+1}\right).\left(1-\dfrac{\sqrt{x}\left(\sqrt{x}-1\right)}{\sqrt{x}-1}\right)\)

\(=\left(1+\sqrt{x}\right)\left(1-\sqrt{x}\right)=1+\sqrt{x}-\sqrt{x}-x=1-x\)

:vvv
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Ling ling 2k7
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Yeutoanhoc
25 tháng 6 2021 lúc 10:31

Hình như sai đề :_:

*Sửa lại:

`(x-2sqrtx+1)/((sqrtx-1)(sqrtx+1))`

`=(sqrtx-1)^2/((sqrtx-1)(sqrtx+1))`

`=(sqrtx-1)/(sqrtx+1)`

Nguyễn Lê Phước Thịnh
25 tháng 6 2021 lúc 11:39

Sửa đề: \(\dfrac{x-2\sqrt{x}+1}{\left(\sqrt{x}-1\right)\left(\sqrt{x}+1\right)}\)

Ta có: \(\dfrac{x-2\sqrt{x}+1}{\left(\sqrt{x}-1\right)\left(\sqrt{x}+1\right)}\)

\(=\dfrac{\left(\sqrt{x}-1\right)^2}{\left(\sqrt{x}-1\right)\left(\sqrt{x}+1\right)}\)

\(=\dfrac{\sqrt{x}-1}{\sqrt{x}+1}\)