( x - 1,7 ) = 2,3

x = 2,3 + 1,7

x = 4

TH1

x-1,7=2,3 => x=4

TH2

x-1,7=-2,3 =>x =-0,6

\(A=\frac{1}{100}-\frac{1}{100.98}-\frac{1}{98.96}-....-\frac{1}{6.4}-\frac{1}{4.2}\)

\(\Rightarrow A=\frac{1}{100}-\left(\frac{1}{100.98}+\frac{1}{98.96}+....+\frac{1}{6.4}+\frac{1}{4.2}\right)\)

\(\Rightarrow A=\frac{1}{100}-\left(\frac{1}{100}-\frac{1}{98}+\frac{1}{98}-\frac{1}{96}+.....+\frac{1}{6}-\frac{1}{4}+\frac{1}{4}-\frac{1}{2}\right)\)

\(\Rightarrow A=\frac{1}{100}-\left(\frac{1}{100}-\frac{1}{2}\right)\Rightarrow A=\frac{1}{100}-\frac{1}{100}+\frac{1}{2}\Rightarrow A=\frac{1}{2}\)

\(A=\frac{1}{100}-\frac{1}{100.98}-\frac{1}{98.96}-...-\frac{1}{6.4}-\frac{1}{4.2}\)

\(A=\frac{1}{100}-\left(\frac{1}{2.4}+\frac{1}{4.6}+...+\frac{1}{96.98}+\frac{1}{98.100}\right)\)

\(A=\frac{1}{100}-\frac{1}{2.2}.\left(\frac{1}{1.2}+\frac{1}{2.3}+...+\frac{1}{48.49}+\frac{1}{49.50}\right)\)

\(A=\frac{1}{100}-\frac{1}{4}.\left(1-\frac{1}{2}+\frac{1}{2}-\frac{1}{3}+...+\frac{1}{48}-\frac{1}{49}+\frac{1}{49}-\frac{1}{50}\right)\)

\(A=\frac{1}{100}-\frac{1}{4}.\left(1-\frac{1}{50}\right)\)

\(A=\frac{1}{100}-\frac{1}{4}.\frac{49}{50}\)

\(A=\frac{2}{200}-\frac{49}{200}=-\frac{47}{200}\)

\(\left(x-1\right)^2+\left|x^2-1\right|=0.\)

Vì \(\hept{\begin{cases}\left(x-1\right)^2\ge0\\\left|x^2-1\right|\ge0\end{cases}}\)

\(\Rightarrow\hept{\begin{cases}x-1=0\\x^2-1=0\end{cases}\Rightarrow x=1}\)

Tìm GTLN của |x-3|+|x-5|

16 nha bạn!

tai sao

gọi A=1/2+1/4+1/8+...+1/1024

2xA=1+1/2+1/4+.....+1/512

2xA-A=(1+1/2+1/4+....+1/512)-(1/2+1/4+1/8+...+1/1024)

A=1-1/1024

=1023/1024

vậy A=1023/1024