Mathematics finale of Lanzhou senior high school entrance examination

(1), b and c are on parabola, 1=9a+3b, -3=a-b, a=-2/3, b=7/3, parabola y = (-2x2+7x)/3;

B on hyperbola, 1=k/3, k=3, hyperbola y = 3/x.

(2) D and C are symmetric about O, and the straight line where D (1, 3) and d C are located is k = 3；;

BC's straight line K = 1, 45 degrees;

When the straight line where point P is located is k= 1/3, the condition is satisfied, and P (3, 1),1= (-18+21)/3, p is on a parabola.

(3), BFDO is a right-angled trapezoid, | bo | = | do |

FD:y =(x+8)/3； FB:y=-3x+ 10，F( 1 1/5， 17/5)；

DB:y=-x+4，FO:y = 17x/ 13；

N(26/ 15，34/ 15)；

DN/NB= 1 1/ 19 .

(1) What are the main courses in the university?