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 6: ( x – 5 ) mũ 4 = ( x – 5 ) mũ 6

Toán Lớp 6: ( x – 5 ) mũ 4 = ( x – 5 ) mũ 6

Comments ( 2 )

  1. Giải:
    (x – 5)^4 = (x – 5)^6
    -> (x – 5)^4 – (x – 5)^6 = 0
    -> (x – 5)^4 . [1 – (x – 5)^2] = 0
    -> (x – 5)^4 = 0 hoặc 1 – (x – 5)^2 = 0
    -> x – 5 = 0 hoặc (x – 5)^2 = 1
    -> x = 5 hoặc x – 5 = ±1
    -> x = 5 hoặc x = 6 hoặc x = 4
    Vậy x ∈ {4; 5; 6}
     

  2. $\\$
    (x-5)^4 = (x-5)^6
    -> (x-5)^4 – (x-5)^6 = 0
    -> (x-5)^4 – (x-5)^4 . (x-5)^2 = 0
    -> (x-5)^4 . [1 – (x-5)^2]=0
    Trường hợp 1 :
    -> (x-5)^4=0
    ->x-5=0
    ->x=0+5
    ->x=5
    Trường hợp 2 :
    ->1-(x-5)^2 =0
    -> (x-5)^2=1-0
    -> (x-5)^2=1
    -> (x-5)^2=1^2 hoặc (x-5)^2=(-1)^2
    ->x-5=1 hoặc x-5=-1
    ->x=1+5 hoặc x=-1+5
    ->x=6 hoặc x=4
    Vậy x=5,x=6,x=4
     

Leave a reply

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

About Ngọc Sa