A)3-2(5-x)(x-5)-2(5+x)²б)(x-y-z)(x-y-z)-(x-y)²в)(x+y+z)(x-y-z)-(x+y-z)(x-y+z)г)(x+y-x)(x-y+z)-(x+y+z)(x-y-z)

Раскроем скобки и упростим выражения:

1) 3 - 2 * (5 - х) * (х - 5) - 2 * (5 + х)^2 = 3 - 2 * (5х - 25 - х^2 + 5х) - 2 * (25 + 10х + х^2) = 3 - 20х + 50 + 2х^2 - 50 - 20х - 2х^2 = -40х + 3;

2) (х - у - z) * (x - y - z) - (x - y)^2 = x^2 - xy - xz - xy + y^2 + yz - xz + yz + z^2 - (x^2 - 2xy + y^2) = x^2 - xy - xz - xy + y^2 + yz - xz + yz + z^2 - x^2 + 2xy - y^2 = -2xz + 2yz + z^2.

3) (x + y + z) * (x - y - z) - (x + y - z) * (x - y + z) = x^2 - xy - xz + xy - y^2 - yz + xz - yz - z^2 - (x^2 - xy + xz + xy - y^2 + yz - xz + yz - z^2) = x^2 - xy - xz + xy - y^2 - yz + xz - yz - z^2 - x^2 + xy - xz - xy + y^2 - yz + xz - yz + z^2 = -4yz.

4) (x + y - z) * (x - y + z) - (x + y + z) * (x - y - z) = x^2 - xy + xz + xy - y^2 + yz - xz + yz - z^2 - (x^2 - xy - xz + xy - y^2 - yz + xz - yz - z^2) = x^2 - xy + xz + xy - y^2 + yz - xz + yz - z^2 - x^2 + xy + xz - xy + y^2 + yz - xz + yz + z^2 = 4yz.