tìm x biết :
a, | x | – $\frac{1}{2}$ = $\frac{1}{3}$ b, | $\frac{4}{3}$ – x | = $\frac{1}{5}$
tìm x biết :
a, | x | – $\frac{1}{2}$ = $\frac{1}{3}$ b, | $\frac{4}{3}$ – x | = $\frac{1}{5}$
`a)|x| – 1/2 = 1/3`
`|x| = 1/3 + 1/2`
`|x| =5/6`
⇒ `x = 5/6` hoặc `x = -5/6`
Vậy `x` ∈ `{ 5/6 ; -5/6}`
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`b)|4/3 – x| = 1/5`
⇒ `4/3 – x = 1/5` hoặc `4/3 – x = -1/5`
`x = 4/3 – 1/5` hoặc `x = 4/3 – (-1/5)`
`x = 17/15` hoặc `x = 23/15`
Vậy `x` ∈ `{ 17/15 ; 23/15}`
`a, |x| – 1/2 = 1/3`
`<=> |x| = 1/3 + 1/2`
`<=> |x| = 5/6`
`<=> x∈{5/6 ; -5/6}`
Vậy `x∈{5/6 ; -5/6}`
`b, |4/3 – x| = 1/5`
`<=>`\(\left[ \begin{array}{l}\frac{4}{3}-x = \frac{1}{5}\\\frac{4}{3}-x = \frac{-1}{5}\end{array} \right.\)
`<=> ` \(\left[ \begin{array}{l}x=\frac{17}{15}\\x=\frac{23}{15}\end{array} \right.\)
Vậy `x∈{17/15 ; 23/15}`