2. Uprosc wyrazenia:
a) -(x + 1) + (2x + 4) =
b) (x + 4) + (2x - 6) =
c) -(2y + 3x) + (-4y + 2x + 1) =
d) -(x - 2xy) - (4x + xy) + (xy-x) =
e) (x^2 + 2x +1) - (x^2 -4x + 3) =