K
Khách

Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.

8 tháng 7 2016

\(\sqrt{\left(1-\sqrt{1993}\right)^2}.\sqrt{1994+2.1993}=\sqrt{\left(1-\sqrt{1993}\right)^2}.\sqrt{\left(\sqrt{1993}+1\right)^2}=\left(\sqrt{1993}-1\right)\left(\sqrt{1993}+1\right)=1993-1=1992\)

11 tháng 7 2018

\(\left(1+\sqrt{1993}\right).\sqrt{1994-2\sqrt{1993}}\)

\(=\left(1+\sqrt{1993}\right).\sqrt{\left(\sqrt{1993}\right)^2-2.\sqrt{1993}+1}\)

\(=\left(1+\sqrt{1993}\right).\sqrt{\left(\sqrt{1993}-1\right)^2}\)

\(=\left(1+\sqrt{1993}\right).\left(\sqrt{1993}-1\right)\)

\(=1992\)

ai tích mình mình tích lại cho

27 tháng 7 2021

a) \(-0,8\sqrt{\left(-0,125\right)^2}=-0,8.\left|-0,125\right|=-0.8.0,125=-\dfrac{1}{10}\)

b) \(\sqrt{\left(-2\right)^6}=\sqrt{\left(\left(-2\right)^3\right)^2}=\left|\left(-2\right)^3\right|=8\)

c) \(\sqrt{\left(\sqrt{3}-2\right)^2}=\left|\sqrt{3}-2\right|=2-\sqrt{3}\)

d) \(\sqrt{\left(2\sqrt{2}-3\right)^2}=\left|2\sqrt{2}-3\right|=3-2\sqrt{2}\)

27 tháng 7 2021

Thanks ạ hihi

8 tháng 9 2023

\(B=\left(\dfrac{4}{1-\sqrt{5}}+\dfrac{1}{2+\sqrt{5}}-\dfrac{4}{3-\sqrt{5}}\right)\left(\sqrt{5}-6\right)\)

\(B=\left[\dfrac{4\left(1+\sqrt{5}\right)}{\left(1-\sqrt{5}\right)\left(1+\sqrt{5}\right)}+\dfrac{2-\sqrt{5}}{\left(2+\sqrt{5}\right)\left(2-\sqrt{5}\right)}-\dfrac{4\left(3+\sqrt{5}\right)}{\left(3-\sqrt{5}\right)\left(3+\sqrt{5}\right)}\right]\left(\sqrt{5}-6\right)\)

\(B=\left[\dfrac{4\left(1+\sqrt{5}\right)}{1-5}+\dfrac{2-\sqrt{5}}{4-5}-\dfrac{4\left(3+\sqrt{5}\right)}{9-5}\right]\left(\sqrt{5}-6\right)\)

\(B=\left[-\dfrac{4\left(1+\sqrt{5}\right)}{4}-\dfrac{2-\sqrt{5}}{1}-\dfrac{4\left(3+\sqrt{5}\right)}{4}\right]\left(\sqrt{5}-6\right)\)

\(B=\left(-1-\sqrt{5}-2+\sqrt{5}-3-\sqrt{5}\right)\left(\sqrt{5}-6\right)\)

\(B=\left(-\sqrt{5}-6\right)\left(\sqrt{5}-6\right)\)

\(B=-\left(\sqrt{5}+6\right)\left(\sqrt{5}-6\right)\)

\(B=-\left(5-36\right)\)

\(B=-\left(-31\right)\)

\(B=31\)

_____________________________

\(\sqrt{48}-\dfrac{\sqrt{21}-\sqrt{15}}{\sqrt{7}-\sqrt{5}}+\dfrac{2}{\sqrt{3}+1}\)

\(=4\sqrt{3}-\dfrac{\sqrt{3}\left(\sqrt{7}-\sqrt{5}\right)}{\sqrt{7}-\sqrt{5}}+\dfrac{2\left(\sqrt{3}-1\right)}{\left(\sqrt{3}-1\right)\left(\sqrt{3}+1\right)}\)

\(=4\sqrt{3}-\sqrt{3}-\dfrac{2\left(\sqrt{3}-1\right)}{2}\)

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

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

25 tháng 11 2021

\(a,=\dfrac{x+3\sqrt{x}+2+2x-4\sqrt{x}-2-5\sqrt{x}}{\left(\sqrt{x}-2\right)\left(\sqrt{x}+2\right)}\\ =\dfrac{3x-6\sqrt{x}}{\left(\sqrt{x}-2\right)\left(\sqrt{x}+2\right)}=\dfrac{3\sqrt{x}\left(\sqrt{x}-2\right)}{\left(\sqrt{x}-2\right)\left(\sqrt{x}+2\right)}=\dfrac{3\sqrt{x}}{\sqrt{x}+2}\\ b,=2a-6b+6b-5a=-3a\)

18 tháng 5 2021

\(\sqrt{\left(5-\sqrt{24}\right)^2}-\sqrt{\left(5+\sqrt{24}\right)^2}\\ =\left|5-\sqrt{24}\right|-\left|5+\sqrt{24}\right|\\ =5-\sqrt{24}-5-\sqrt{24}\\ =-2\sqrt{24}=-4\sqrt{6}\)

18 tháng 5 2021

`\sqrt((5-\sqrt24)^2) - \sqrt((5+\sqrt24)^2)`

`=|5-\sqrt24|-|5+\sqrt24|`

`=5-\sqrt24-5-\sqrt24`

`=-2\sqrt24`

`=-4\sqrt6`

19 tháng 7 2023

   (\(\dfrac{1}{\sqrt{2}-1}\) - \(\dfrac{1}{\sqrt{2}+1}\)): \(\sqrt{3-2\sqrt{2}}\)

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

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

= 2(\(\sqrt{2}\)  - 1)

= 2\(\sqrt{2}\) - 2

21 tháng 9 2023

\(a,\sqrt{\left(2-\sqrt{5}\right)^2}-\sqrt{\left(1+\sqrt{5}\right)^2}\)

\(=\left|2-\sqrt{5}\right|-\left|1+\sqrt{5}\right|\)

\(=\sqrt{5}-2-\left(1+\sqrt{5}\right)\)

\(=\sqrt{5}-2-1-\sqrt{5}\)

\(=-3\)

\(b,\dfrac{3-5\sqrt{3}}{\sqrt{3}-5}+6\sqrt{\dfrac{4}{3}}\)

\(=\dfrac{\sqrt{3}\left(\sqrt{3}-5\right)}{\sqrt{3}-5}+6\cdot\dfrac{\sqrt{4}}{\sqrt{3}}\)

\(=\sqrt{3}+\dfrac{12}{\sqrt{3}}\)

\(=\sqrt{3}+\dfrac{12\sqrt{3}}{3}\)

\(=\sqrt{3}+4\sqrt{3}\)

\(=5\sqrt{3}\)

#\(Toru\)

21 tháng 9 2023

\(\sqrt{\left(2-\sqrt{5}\right)^2}-\sqrt{\left(1+\sqrt{5}\right)^2}\\ =\left|2-\sqrt{5}\right|-\left|1+\sqrt{5}\right|\\ =\sqrt{5}-2-1-\sqrt{5}\\ =-2-1\\ =-3\)

\(\dfrac{3-5\sqrt{3}}{\sqrt{3}-5}+6\sqrt{\dfrac{4}{3}}\\ =\dfrac{\sqrt{3}\left(\sqrt{3}-5\right)}{\sqrt{3}-5}+4\sqrt{3}\\ =\sqrt{3}+4\sqrt{3}\\ =5\sqrt{3}\)

25 tháng 6 2023

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

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

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

\(=5-2\sqrt{3}\)

25 tháng 6 2023

\(-\sqrt{3}-\sqrt{3}=-2\sqrt{3}\) 

Chứ cj