\(3x^2+6x+3-2y^2=3x^2+3x+3x+3-3y^2\)
\(=\left(3x^2+3x\right)+\left(3x+3\right)-3y^2=3x.\left(x+1\right)+3.\left(x+1\right)-3y^2\)
\(=\left(x+1\right)\left(3x+3\right)-3y^2=\left(x+1\right).3.\left(x+1\right)-3y^2\)
\(=3\left(x+1\right)^2-3y^2=3.\left[\left(x+1\right)^2-y^2\right]\)
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3x2 + 6x + 3 - 3y2
= 3(x2 + 2x + 1 - y2)
= \(3\left[\left(x+1\right)^2-y^2\right]\)
= \(3\left[\left(x+1+y\right)\left(x+1-y\right)\right]\)
3x2 + 6x +3 - 3y2 =(3x2 + 6x +3) - 3y2
= 3(x2 + 2x +1) -3y2
= 3(x+1)2 - 3y2
=3\(\left[\left(x+1\right)^2-y^2\right]\)
= 3 (x+1+y)(x+!-y)
\(3x^2+6x+3-3y^2\)
\(\Leftrightarrow3\left(x^2+2x+1-y^2\right)\)
\(\Leftrightarrow3\left[\left(x+1\right)^2-y^2\right]\)
\(\Leftrightarrow3\left(x+1-y\right)\left(x+1+y\right)\)