Question

Giải các phương trình sau
a) x(x-1)+2x²-2=0
b) 9x²-1=(3x+1)(2x-3)
 

Answer 1

a: \(x\left(x-1\right)+2x^2-2=0\)

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

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

=>(x-1)(3x+2)=0

=>\(\left[{}\begin{matrix}x=1\\x=-\dfrac{2}{3}\end{matrix}\right.\)

b: \(9x^2-1=\left(3x+1\right)\left(2x-3\right)\)

=>\(\left(3x+1\right)\left(3x-1\right)-\left(3x+1\right)\left(2x-3\right)=0\)

=>\(\left(3x+1\right)\left(3x-1-2x+3\right)=0\)

=>(3x+1)(x+2)=0

=>\(\left[{}\begin{matrix}x=-\dfrac{1}{3}\\x=-2\end{matrix}\right.\)

Answer 2

a: 

=>

=>

=>(x-1)(3x+2)=0

=>⎡⎣x=−13x=−2