Question

Proszę o rozwiązanie.
(x+y)(x-y+1) =
(x-y)(x+y-1) =
(x-y)(x-2y-1) =
(2a-b)(b+1) =
(2a-3b)(3b+3)=
(2x-4y)(3x-2) =
(-2x+y)(6x-4) =

Answer 1

(x+y)(x-y+1) = x^2-xy+x+xy-y^2+y= x^2+x-y^2+y
(x-y)(x+y-1) =x^2+xy-x-xy-y^2+y=x^2-x-y^2+y
(x-y)(x-2y-1) =x^2-2xy-x-xy+2y^2+y=x^2-3xy-x+2y^2+y
(2a-b)(b+1) =2ab+2a-b^2-b
(2a-3b)(3b+3)=6ab+6a-9b^2-9b
(2x-4y)(3x-2) =6x^2-4x-12xy+8y
(-2x+y)(6x-4) =-12x^2+8x+6xy-4y

Answer 2

(x+y)(x-y+1)=x(x-y+1) +y(x-y+1)=x^2-xy+x + xy-y^2+y=x^2+x -y^2+y
(x-y)(x+y-1)=x(x+y-1) -y(x+y-1)=x^2+xy-x -xy-y^2+y=x^2-x -y^2+y
(x-y)(x-2y-1)=x(x-2y-1) -y(x-2y-1)=x^2-2xy-x -xy+2y^2+y=x^2-3xy-x+2y^2+y
(2a-b)(b+1)=2ab+2a-b^2-b
(2a-3b)(3b+3)=6ab+6a-9b^2-9b
(2x-4y)(3x-2)=6x^2-4x-12xy+8y
(-2x+y)(6x-4)= -12x^2+8x+6xy-4y