Register Now

Lost Password

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

Toán Lớp 8: Tìm x x(x-2)+x-2=0 (x-1)^2+x(4-x)=0

Home/ Toán Lớp 8: Tìm x x(x-2)+x-2=0 (x-1)^2+x(4-x)=0

Toán Lớp 8: Tìm x x(x-2)+x-2=0 (x-1)^2+x(4-x)=0

Nhân Tháng Mười 29, 2022 Toán học 2 Comments 0 views

Toán Lớp 8: Tìm x
x(x-2)+x-2=0
(x-1)^2+x(4-x)=0

Comments ( 2 )

maianhnhiquynh
29 Tháng Mười, 2022 at 1:23 sáng

Reply

#Sad

a)

x(x-2)+x-2 = 0

⇔ x(x-2)+(x-2) = 0

⇔ (x+1)(x-2) = 0

⇔ \(\left[ \begin{array}{l}x+1=0\\x-2=0\end{array} \right.\)

⇔ \(\left[ \begin{array}{l}x=-1\\x=2\end{array} \right.\)

\text{Vậy S=} {-1; 2}

b)

(x-1)^2+x(4-x) = 0

⇔ x^2-2x+1+4x-x^2 = 0

⇔ (x^2-x^2)+(-2x+4x)+1 = 0

⇔ 2x+1 = 0

⇔ 2x = -1

⇔ x = -(1)/(2)

\text{Vậy S=} {-(1)/(2)}
huyenmi76
29 Tháng Mười, 2022 at 1:22 sáng

Reply

a. x(x-2)+x-2=0

<=> x^2 -2x+x-2=0

<=> x^2 -x-2=0

<=> (x-2)( x+1)=0

<=> \(\left[ \begin{array}{l}x=2\\x=-1\end{array} \right.\)

=> x∈{2;-1}

b. (x-1)^2+x(4-x)=0

<=> x^2-x-1(x-1)+x(4-x)=0

<=> x^2 -x-x+1+x(4-x)=0

<=> x^2 -2x+1-x^2 +4x=0

<=> -2x+1+4x=0

<=> 2x=-1

<=> x=-1/2

Leave a reply

About Nhân