1. x=2代入方程得
4+2p+q+1=0
∴q=-2p-5
2. ⊿=p²-4q
=p²-4(-2p-5)
=p²+8p+20
=p²+8p+16+4
=(p+4)²+4>0
∴抛物线与x轴又两个交点