Thi tự làm ko ai giúp bạn đc đôu:)
I 7 - x I = 1/5
➜ 7 - x = 1/5 hoặc 7-x = - 1/5
x = 7 - 1/5 x= 7 - ( - 1/5 )
x = 7/ 1 - 1/5 x = 7/1 - ( -1/5 )
x = 35/5 - 1/5 x = 35/5 - ( -1/5)
x = 34/5 x = 36/5
Vậy x = 34/5 hoặc 36/5
\(\left|7-x\right|=\dfrac{1}{5}\)
\(\text{Vậy }7-x=\dfrac{1}{5}\)
\(x=7-\dfrac{1}{5}=\dfrac{34}{5}\)
\(\text{hoặc }7-x=\dfrac{-1}{5}\)
\(x=7-\left(\dfrac{-1}{5}\right)=\dfrac{36}{5}\)
\(\Rightarrow x\in\left\{\dfrac{34}{5};\dfrac{36}{5}\right\}\)