\(4x^2+4x-3\)
\(4x^2+4x+1-4\)
\(\left(2x+1\right)^2-2^2\)
\(\left(2x+1-2\right)\left(2x+1+2\right)\)
\(\left(2x-1\right)\left(2x+3\right)\)
Trả lời:
4x2 + 4x - 3
= [ ( 2x )2 + 2.2x.1 + 1 ] - 4
= ( 2x + 1 )2 - 4
= ( 2x + 1 - 2 ) ( 2x + 1 + 2 )
= ( 2x - 1 ) ( 2x + 3 )