\(=\left(1+2+3+...+1000\right)\times\left[\left(0,75-\dfrac{3}{4}\right)\cdot0,4\right]\)

\(=\left(1+2+3+...+1000\right)\times0=0\)

\(=4-\dfrac{12}{5}\sqrt{5}-6+\dfrac{18}{5}\sqrt{5}+2\sqrt{5}-6\)

\(=-8+\dfrac{16}{5}\sqrt{5}\)

Đề bài: Tìm x

\(\frac{2}{3}x-0.4=\frac{1}{5}\)

\(\frac{2}{3}x-0=\frac{1}{5}\)

\(\frac{2}{3}x=\frac{1}{5}\)

\(x=\frac{1}{5}\div\frac{2}{3}\)
\(x=\frac{1}{5}.\frac{3}{2}\)

\(x=\frac{3}{10}\)

Vậy \(x=\frac{3}{10}.\)

Bài làm:

\(\frac{2}{3}x-0.4=\frac{1}{5}\)

\(\Leftrightarrow\frac{2}{3}x-\frac{2}{5}=\frac{1}{5}\)

\(\Leftrightarrow\frac{2}{3}x=\frac{3}{5}\)

\(\Leftrightarrow x=\frac{3}{5}\div\frac{2}{3}\)

\(\Rightarrow x=\frac{9}{10}\)

Học tốt!!!!

\(\frac{2}{3}x-0,4=\frac{1}{5}\)

\(\frac{2}{3}x=\frac{1}{5}+0,4\)

\(\frac{2}{3}x=\frac{3}{5}\)

\(x=\frac{9}{10}\)

TA CÓ :abcdefg+hjklzxcv=vbnm

1+1=2

\(0,16\text{ : }x=2-0,4\)

\(0,16\text{ : }x=1,6\)

             \(x=0,16\text{ : }1,6\)

             \(x=0,1\)

\(\text{Chúc bạn học tốt !}\)

0,16 : x = 2 - 0,4

0,16 : x = 1,6

x= 0,16 : 1,6 

x= 0,1

0,16:x=2-0,4

0,16:x=1,6

      x  =0,16:1,6

      x  =0,1

3.2 : 2/10 + 0.4 : 12.5% + 2.4 : 0.25 + 1.6 × 2 = 3.2 : 0,2 + 0.4 : 0,125 + 2.4 : 0.25 + 1.6 × 2

= 16 + 3,2 + 9,6 + 3,2 = 32

Đang gấp nên mn trả lời giúp e đc ko ạ 💕

3.2 : 2/10 + 0.4 : 12.5% + 2.4 : 0.25 + 1.6 x 2

= 16 + 3.2 + 9.6 + 3.2

= 19.2 + 9.6 + 3.2

=  28.8 + 3.2

= 32

Lời giải:

\(\sqrt[-0,4]{(-0,4)^2}=\sqrt[-0,4]{\frac{4}{25}}=(\frac{4}{25})^{\frac{1}{-0,4}}=(\frac{4}{25})^{\frac{-5}{2}}=\frac{1}{(\frac{4}{25})^{\frac{5}{2}}}=\frac{1}{\sqrt{(\frac{4}{25})^5}}=\frac{1}{(\frac{2}{5})^5}=\frac{3125}{32}\)

\(\sqrt[-0.4]{\left(-0.4\right)^2}=\sqrt[-0.4]{\dfrac{4}{25}}=\left(\dfrac{4}{25}\right)^{\dfrac{1}{-0.4}}=\dfrac{3125}{32}\)