Question

\(2x\left(5x-1\right)-\left(3x-1\right)\left(3x+1\right)=2-2x\)
giải pt trên

 

Answer 1

\(2x\left(5x-1\right)-\left(3x-1\right)\left(3x+1\right)=2-2x\)

=>\(10x^2-2x-9x^2+1=2-2x\)

=>\(x^2-2x+1-2+2x=0\)

=>\(x^2-1=0\)

=>\(x^2=1\)

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

Answer 2

`2x(5x-1) - (3x-1)(3x+1)=2-2x`

`=> 10x^2 - 2x - [(3x)^2 - 1^2] - 2 + 2x = 0`

`=> 10x^2 - 2x - (9x^2 - 1) - 2 + 2x = 0`

`=> 10x^2 - 2x - 9x^2 + 1 - 2 +2x=0`

`=> (10x^2-9x^2)+(-2x+2x)+(1-2)=0`

`=> x^2-1=0`

`=>x^2=1`

`=>x=+-1`

Vậy: `x=+-1`