Let f (x) = x2-3x + 1, then f (a) - f (- a) is equal to =?, Urgent,,

Let f (x) = x2-3x + 1, then f (a) - f (- a) is equal to =?, Urgent,,

f(x)=x2-3x+1
f(a)=a2-3a+1
f(-a)=a2+3a+1
f(a)-f(-a)=-6a