Maths (f.2)

1.2(x-y)²+8(x-y)+8
=2[(x-y)+2]²
=2(x-y+2)²

2.x²-4y²-3x-6y
=(x+2y)(x-2y)-3(x+2y)
=(x+2y)[(x-2y)-3]
=(x-2y-3)(x+2y)

1.2(x-y)(2次方)+8(x-y)+8
=2(x(2次方)-y(2次方))+8x-8y+8
=2x(2次方)-y(2次方)+8x-8y+8
=10x(2次方)-9y(2次方)+8

2.x(2次)-4y(2次)-3x-6y
=2x-8y-3x-6y
=-x-14y

1.
2(x - y) ^ 2 + 8(x - y ) + 8
= 2 [(x - y)^ 2 + 4(x - y) + 4]
= 2 [(x - y) - 2]^2
= 2(x - y - 2)^2

2.
x^ 2 - 4y^ 2 - 3x - 6y
= ( x + 2y)(x - 2y) - 3( x - 2y)
= (x - 2y)(x + 2y - 3)