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 8: tìm x x^3=x^2 x(x^2+1)=10(x^2+1)

Toán Lớp 8: tìm x
x^3=x^2
x(x^2+1)=10(x^2+1)

Comments ( 2 )

  1. x^3=x^2
    x^3-x^2=0
    x^2.(x-1)=0
    TH1
    x^2=0
    x=0
    TH2
    x-1=0
    x=1
    x.(x^2+1)=10(x^2+1)
    x.(x^2+1)-10.(x^2+1)=0
    (x^2+1)(x-10)=0
    TH1
    x^2+1=0
    x^2=-1
    x∈{∅}
    TH2
    x-10=0
    x=10

  2. x^3=x^2
    ⇔x^3-x^2=0
    ⇔x^2(x-1)=0
    ⇔x=0
    ⇔x-1=0⇔x=1
    Vậy x={0,1}
    b,
    x(x^2+1)=10(x^2+1)
    ⇔x(x^2+1)-10(x^2+1)=0
    ⇔(x^2+1)(x-10)=0
    ⇔x^2+1=0⇔x không thỏa mãn
    x-10=0⇔x=10
    Vậy x=10
     

Leave a reply

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