Tìm x ∈ Z
a) $\frac{1}{2}$ < $\frac{5}{x}$ < $\frac{1}{3}$
b) $\frac{-8}{25}$ < $\frac{x}{40}$ < $\frac{-7}{5}$
Tìm x ∈ Z a) $\frac{1}{2}$ < $\frac{5}{x}$ < $\frac{1}{3}$ b) $\frac{-8}{25}$ < $\frac{x}{40}$ < $\frac{-7}{5}$
By Eden
By Eden
Tìm x ∈ Z
a) $\frac{1}{2}$ < $\frac{5}{x}$ < $\frac{1}{3}$
b) $\frac{-8}{25}$ < $\frac{x}{40}$ < $\frac{-7}{5}$
Đáp án:
1/2<5/x<1/3=>5/10<5/x<5/15
=>10<x<15
vì x∈Z nên x∈{11;12;13;14}
b, -8/25<x/40<-7/5
-64/200<5x/200<-280/200
=>-64<5x<-280
=>-64/5<x<-280/5
=>-13≤x<-56
Vì x∈Z nên x∈{-14;-15;……………….;-54;-55}
cho mình xin hay nhất nha
thank you very much
Đáp án:
Giải thích các bước giải:
a
$\frac{1}{2}$<$\frac{5}{x}$<$\frac{1}{3}$ => $\frac{5}{10}$<$\frac{5}{x}$<$\frac{5}{15}$ vì x ∈ Z nên x ∈ {11;12;13;14}
b
-8/25<x/40<-7/5
64/200<5x/200<-280/200=>-64<5x<-280=>-64/5<x<-280/5
=>-13≤x<-56
Vì x ∈ Z nên x ∈{ -14;-15,-16..;-54;-55}