Register Now

Login

Lost Password

Lost your password? Please enter your email address. You will receive a link and will create a new password via email.

222-9+11+12:2*14+14 = ? ( )

Toán Lớp 7: -8/4<-6/...<-8/6, giúp mik với ạ

Toán Lớp 7: -8/4<-6/...<-8/6, giúp mik với ạ

Comments ( 2 )

  1. – Mk xin ctlhn ạ !!
              Gọi $\frac{-6}{…}$ là $\frac{-6}{x}$
        $\frac{-8}{4}$ < $\frac{-6}{x}$ < $\frac{-8}{6}$ 
    ⇒ -2 < $\frac{-6}{x}$ < $\frac{-4}{3}$ 
    ⇒ $\frac{-24}{12}$ < $\frac{-24}{4x}$ < $\frac{-24}{18}$
    ⇒ 12 < 4x < 18
    ⇒ 4x ∈ { 13 ; 14 ; 15 ; 16 ; 17 }
    Vì x ∈ Z
       x = 4
                 Vậy x = 4

  2. $\text{Gọi số cần tìm là x (x khác 0)}$
    -8/4 < -6/x < -8/6
    $\Rightarrow$ -8/4 < -6/x < -4/3
    $\Rightarrow$ -24/12 < -24/4x. < -24/18
    $\Rightarrow$ 12 < 4x < 18
    $\Rightarrow$ x = 4
    $\text{Vậy}$ x = 4
     

Leave a reply

222-9+11+12:2*14+14 = ? ( )

About Thanh Thu