Question

tìm các số nguyên x biết :

a) 2/-5 < x/10 < 1/4          b)-2/3 < x/8 < -1/6

Mình đag cần rất gấp

Answer 1

a) \(\frac{2}{-5}< \frac{x}{10}< \frac{1}{4}\)

\(\Rightarrow\frac{-8}{20}< \frac{2x}{20}< \frac{5}{20}\)

\(\Rightarrow-8< 2x< 5\)

\(\Rightarrow-4< x< 2,5\)

Vì \(x\inℤ\) nên \(x\in\left\{-3;-2;-1;0;1;2\right\}\)

b) \(-\frac{2}{3}< \frac{x}{8}< -\frac{1}{6}\)

\(\Rightarrow\frac{-16}{24}< \frac{3x}{24}< \frac{-4}{24}\)

\(\Rightarrow-16< 3x< -4\)

\(\Rightarrow3x\in\left\{-15;-12;-9;-6\right\}\)

\(\Rightarrow x\in\left\{-5;-4;-3;-2\right\}\)

Answer 2

a) x=1

b)x=-3,-2