problems with integration

[resolved]

in textbook CAS mode,

int(-3*(x-3)^2 + 3*(x-9)^2 + 21*(x-3) + 18*(x-9)-24)

the result I get is:

-(x-3)^3 + (x-9)^3 + 21*(1/2 * x^2 - 3*x ) + 18*(1/2*x^2 - 9*x) - 24*x

if I integrate the expression by hand I get:

-(x-3)^3 + (x-9)^3 + 21/2 * (x-3)^2 + 9*(x-9)^2 - 24* x

HP Prime expression simplifies to:

(3*x^2 - 66*x - 1404)/2

my integration simplifies to:

(3*x^2 - 66*x +243)/2

clearly, these are not the same results....

what was the result you got by hand????