B=\(\left(x-y\right)^2-\left(x+y\right)+4xy\)
\(=x^2-2xy+y^2-x-y+4xy\)
\(=x^2+2xy+y^2-x-y\)
\(=\left(x+y\right)^2-\left(x+y\right)\)
C=\(\left(2x+3\right)\left(2x-3\right)-\left(2x-3\right)^2\)
\(=\left(2x\right)^2-3^2-\left[\left(2x\right)^2-12x+3^2\right]\)
\(=4x^2-9-4x^2+12x-9\)
\(=12x-18\)
\(=3\left(4x-6\right)\)
A=(x+1)2−(x+1)(x−1)=(x+1)2−(x+1)(x−1)
=x2+2x+1−x2+1=x2+2x+1−x2+1
=2x+2
B=(x−y)2−(x+y)+4xy(x−y)2−(x+y)+4xy
=x2−2xy+y2−x−y+4xy=x2−2xy+y2−x−y+4xy
=x2+2xy+y2−x−y=x2+2xy+y2−x−y
=(x+y)2−(x+y)=(x+y)2−(x+y)
C=(2x+3)(2x−3)−(2x−3)2(2x+3)(2x−3)−(2x−3)2
=(2x)2−32−[(2x)2−12x+32]=(2x)2−32−[(2x)2−12x+32]
=4x2−9−4x2+12x−9=4x2−9−4x2+12x−9
=12x−18=12x−18
=3(4x−6)
A\(=\left(x+1\right)^2-\left(x+1\right)\left(x-1\right)\)
\(=x^2+2x+1-x^2+1\)
\(=2x+2\)
