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: a. x^3 – 7x + 6 b, x^3 – 7x^2 + 6

Toán Lớp 8: a. x^3 – 7x + 6
b, x^3 – 7x^2 + 6

Comments ( 2 )

  1. x^3 – 7x + 6
    = x^3 – x^2 + x^2 – x – 6x + 6
    = x^2(x-1)+x(x-1)-6(x-1)
    = (x-1)(x^2+x-6)
    = (x-1)(x^2+3x-2x-6)
    = (x-1)[x(x+3)-2(x+3)]
    = (x-1)(x+3)(x-2)
    ………………………………………………..
    x^3 – 7x^2 + 6
    = x^3 – x^2 – 6x^2 + 6x – 6x + 6
    = x^2(x-1) – 6x(x-1)-6(x-1)
    = (x-1)(x^2-6x-6)

  2. Lời giải:
    a. x^(3)-7x+6
    =x^(3)+2x^(2)-2x^(2)-3x-4x+6
    =x^(3)-2x^(2)+2x^(2)-4x-3x+6
    =x^(2)(x-2)+2x(x-2)-3(x-2)
    =(x-2)(x^(2)+2x-3)
    =(x-2)(x^(2)+3x-x-3)
    =(x-2)(x+3)(x-1)
    b. x^(3)-7x^(2)+6
    =x^(3)-x^(2)-6x^(2)+6x-6x+6
    =x^(2)(x-1)-6x(x-1)-6(x-1)
    =(x-1)(x^(2)-6x-6)

Leave a reply

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

About Khánh Ly