Multiplying the identity by
(s−p)(s−q)(s−r) gives
1=A(s−q)(s−r)+B(s−p)(s−r)+C(s−p)(s−q). Setting
s=p,q,r, in turn, yields
A1B1C1=(p−q)(p−r),=(q−p)(q−r),=(r−p)(r−q).
Adding and expanding gives
A1+B1+C1=p2+q2+r2−pq−pr−qr. By Vieta’s formulas,
p+q+r=22 and
pq+pr+qr=80, so
p2+q2+r2=222−2(80)=324. Therefore the requested value is
324−80=244.
Thus,
B is the correct answer.