Тождественные преобразования выражений 1) a^2-c^2-a-c= 2) p^2-k^2-2k+2p= 3) (x-y)^2-4p^2= 4) (2x-y)^2-x^2=

1) a²-c²-a-c = (a -c)(a+c)-(a+c) = (a+c)(a-c-1)
2) p²-k²-2k+2p = (p-k)(p+k)+2(p-k) = (p-k)(p+k+2)
3) (x-y)²-4p² = (x-y-2p)(x-y+2p)
4) (2x-y)²-x² = (2x-y-x)(2x-y+x) = (x-y)(3x-y)