(2x-1)2-36=0
(2x-1)2-62=0
(2x+5)(2x-7)=0
2x+5=0 2x=-5 x=\(\frac{-5}{2}\) | 2x-7=0 2x=7 x=\(\frac{7}{2}\) |
Cách 2
(2x-1)2-36=0
4x2-4x+1-36=0
4x2-4x-35=0
4(x2-x-\(\frac{35}{4}\))=0
\(4\left(x^2+\frac{5}{2}x-\frac{7}{2}x-\frac{35}{4}\right)=0\)
\(4\left[x\left(x+\frac{5}{2}\right)-\frac{7}{2}\left(x+\frac{5}{2}\right)\right]=0\)
\(4\left[\left(x-\frac{7}{2}\right)\left(x+\frac{5}{2}\right)\right]=0\)
\(x-\frac{7}{2}=0\) \(x=\frac{7}{2}\) | \(x+\frac{5}{2}=0\) \(x=-\frac{5}{2}\) |