Giải các pt sau:a, (x- 1)2= 2(x2- 1)b, 2(x+ 2)2- 3- 8= 0c, (x- 1)(x2+ 5x- 2)- 3x+ 1= 0d, (x- 3)2= (2x+ 7)2 e, (x2- 2)(4x- 3)= (x2- 2)(x- 12)f, (x+ 2)(3- 4x)= x2+ 4x+ 4g, x2- 3x+ 2= 0h, x2+ 7x+ 12= 0i, x2- 3x- 10=...
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Giải các pt sau:
a, (x- 1)2= 2(x2- 1)
b, 2(x+ 2)2- 3- 8= 0
c, (x- 1)(x2+ 5x- 2)- 3x+ 1= 0
d, (x- 3)2= (2x+ 7)2
e, (x2- 2)(4x- 3)= (x2- 2)(x- 12)
f, (x+ 2)(3- 4x)= x2+ 4x+ 4
g, x2- 3x+ 2= 0
h, x2+ 7x+ 12= 0
i, x2- 3x- 10= 0
a) (x-1)2=2(x2-1)
<=> x2-2x+1=2x2-2
<=> x2-2x+1-2x2+2=0
<=> -x2-2x+3=0
<=> -x2+3x-x+3=0
<=> -x(x-3)-(x-3)=0
<=> (x-3)(-x-1)=0
\(\Leftrightarrow\orbr{\begin{cases}x-3=0\\-x-1=0\end{cases}\Leftrightarrow\orbr{\begin{cases}x=3\\-x=1\end{cases}\Leftrightarrow}\orbr{\begin{cases}x=3\\x=-1\end{cases}}}\)