Question

tìm x biết x²-2x+3=0

Answer 1

X^2-2X+3=0

=> X^2+x-3x+3=0

=>x(x+1)-3(X+1)=0

<=>X-3=0 hoặc X+1=0

<=> x=3 hoặc x=-1

Tik nha!!

Answer 2

\(x^2-2x+3=0\)

\(\Leftrightarrow x^2-3x+x-3=0\)

\(\Leftrightarrow x\left(x-3\right)+\left(x-3\right)=0\)

\(\Leftrightarrow\left(x+1\right)\left(x-3\right)=0\)

\(\Leftrightarrow\left[{}\begin{matrix}x+1=0\\x-3=0\end{matrix}\right.\)

\(\Leftrightarrow\left[{}\begin{matrix}x=-1\\x=3\end{matrix}\right.\)

Vậy ...............

Answer 3

Ta có:

\(x^2-2x+3=0\)

\(\Leftrightarrow\left(x-1\right)^2+2=0\)

\(\Leftrightarrow\left(x-1\right)^2=-2\) (vô lí).

Vậy x \(\in\varnothing\).