Rút gọn biểu thức: (x - 3)(x + 5) - (x - 2)(x + 2)

a.(x-3)(x+5)-(x-2)(x+2)
b.(1/4x-y)(x^2+4xy+16y^2)+4(4y^3-1/16x^3+1)
c.(x-2)^2+(x+3)^2-2(x-1)(x+1)
d.(x-2)^2+(x-1)(x^2+x+1)+x(x-2)(x+2)