Δ<0
х^2-(2p+2)x+3p+7≤ 0
Δ=(2p+2)²-4*1*(3p+7)=4p²+8p+4-4(3p+7)=4p²+8p+4-12p-28=4p²-4p-24
4p²-4p-24 ≤0
Δp=16-4*4*(-24)=16-16*(-24)=16+384=400
√Δp=20
p1=( 4-20)/8=-16/8=-2
p2(4+20)/8=24/8=3
p∈(-∞,-2>u<3,+∞)
