1.

0,2 . \(\sqrt{100}\) - \(\sqrt{\dfrac{16}{25}}\)

= 0,2 . 10 - \(\dfrac{4}{5}\)

= 2 - \(\dfrac{4}{5}\)

= \(\dfrac{6}{5}\)

1/ \(0,2.\sqrt{100}-\sqrt{\dfrac{16}{25}}\)

\(=0,2.10-0,8\)

\(=2-0,8=1,2\)

2/ \(\dfrac{2^7.9^3}{6^5.8^2}\)

\(=\dfrac{93312}{497664}=\dfrac{3}{16}=0,1875\)

3/ \(\sqrt{0,01}-\sqrt{0,25}\)

\(=0,1-0,5\)

\(=-0,4\)

4/ \(0,5.\sqrt{100}-\sqrt{\dfrac{1}{4}}\)

\(=0,5.10-0,5\)

\(=5-0,5=4,5\)

5/ \(7.\sqrt{0,01}+2.\sqrt{0,25}\)

\(=7.0,1+2.0,5\)

\(=0,7+1=1,7\)

6/ \(0,5.\sqrt{100}-\sqrt{\dfrac{1}{25}}\)

\(=0,5.10-0,2\)

\(=5-0,2=4,8\)

a)\(\sqrt{0,01}-\sqrt{0,25}\)

=\(\sqrt{\left(0,1\right)^2}-\sqrt{\left(0,5\right)^2}\)

= 0,1 - 0,5 = - 0,4

b)\(0,5.\sqrt{100}-\sqrt{\dfrac{1}{4}}\)

= 5 - 0,5

= 4,5.

a) 0,1 - 0,5 = -0,4

b)0,5 . 10 - 0,5 = 5 - 0,5 = 4,5

thầy thông cảm máy em không có dấu căn.

a) \(\sqrt{0,01}-\sqrt{0,25}=\sqrt{\left(0,1\right)^2}-\sqrt{\left(0,5\right)^2}=0,1-0,5=-0,4\)b) \(0,5\sqrt{100}-\sqrt{\frac{1}{4}}=0,5\sqrt{10^2}-\sqrt{\left(\frac{1}{2}\right)^2}=0,5.10-\frac{1}{2}=5-\frac{1}{2}=\frac{9}{2}\)

a) \(\sqrt{0,01}+\sqrt{0,25}=0,1\cdot0,5=0,05\)

b) \(0,5\sqrt{100}-\frac{\sqrt{1}}{4}=0,5\cdot10-\frac{1}{4}=5-\frac{1}{4}=\frac{19}{4}\)

a/ \(\sqrt{0,01}-\sqrt{0,25}=0,1-0,5=-0,4\)

b/ \(0,5\sqrt{100}-\frac{\sqrt{1}}{4}=0,5.10-\frac{1}{2}=5-\frac{1}{2}=\frac{9}{2}\)

\(\)a)

\(\sqrt{0,01}-\sqrt{0,25}=\sqrt{\frac{1}{100}}-\sqrt{\frac{1}{4}}=\frac{1}{10}-\frac{1}{2}=\frac{1}{10}-\frac{5}{10}=\frac{-4}{10}=\frac{-2}{5}\)

b)

\(0,5.\sqrt{100}-\sqrt{\frac{1}{4}}=0,5.10-\frac{1}{2}=5-\frac{1}{2}=\frac{10}{2}-\frac{1}{2}=\frac{9}{2}\)

ai k mình mình k lại

a) \(\sqrt{0,01}=0,1;\sqrt{0,25}=0,5\)= 0,1-0,5 = -0,4 

b)  = 0,5 x 10 - \(\frac{1}{2}\)= 4,5 . ( Đơn giản nhỉ :) )

bài này bn trục căn thức mẫu nhé

\(P=\dfrac{1-\sqrt{2}}{1-2}+\dfrac{\sqrt{2}-\sqrt{3}}{2-3}+...+\dfrac{\sqrt{99}-\sqrt{100}}{99-100}\)

\(P=\dfrac{1-\sqrt{2}+\sqrt{2}-\sqrt{3}+....+\sqrt{99}-\sqrt{100}}{-1}=\dfrac{1-\sqrt{100}}{-1}=\sqrt{100}-1\)

\(=10-1=9\)

`=(\sqrt1-\sqrt2)/(1-2)+(\sqrt2-\sqrt3)/(2-3)+.....+(\sqrt99-\sqrt100)/(99-100)`

`=\sqrt2-\sqrt1+\sqrt3-\sqrt2+.....+\sqrt100-\sqrt99`

`=-\sqrt1+\sqrt100=-1+10=9`

Ta có: \(\dfrac{1}{\sqrt{1}+\sqrt{2}}+\dfrac{1}{\sqrt{2}+\sqrt{3}}+\dfrac{1}{\sqrt{3}+\sqrt{4}}+...+\dfrac{1}{\sqrt{99}+\sqrt{100}}\)

\(=-1+\sqrt{2}-\sqrt{2}+\sqrt{3}-\sqrt{3}+2-...-\sqrt{99}+10\)

=10-1=9

a) \(\sqrt{0.01}-\sqrt{0.25}=0,1-0,5=-0,4\)

b)\(0,5.\sqrt{100}-\sqrt{\frac{1}{4}}=0,5.10-0,5=4,5\)

a, =2.0,1-0,5                                  b,=\(\left(15\dfrac{1}{4}-25\dfrac{1}{4}\right):\left(-\dfrac{5}{7}\right)\)

    =0,2-0,5                                        =  -10:(\(\dfrac{-5}{7}\))

    =-0,3                                             = 14

           c, \(=\dfrac{5^4.\left(4.5\right)^4}{\left(5^2\right)^4.4^5}=\dfrac{5^4.4^4.5^4}{5^8.4^5}=\dfrac{1}{4^{ }}\)

a, = \(\sqrt{2}\)/2 - 1/2 = \(\sqrt{2}-1\)/2

b, = 0,5 . 10 - 1/2 = 5 - 1/2 =9/2

Đáp án là: 

a) = \(\frac{-1+\sqrt{2}}{2}\) .

b) = \(\frac{9}{2}\) .