To have real roots, the discriminant must be ≥ 0
So
(2p+2)^2 - 4 (3/4) ( p^2 + 2) ≥ 0
4p^2 + 8p + 4 - 3p^2 - 6 ≥ 0
p^2 + 8p - 2 ≥ 0 complete the square on p
p^2 + 8p + 16 ≥ 2 + 16
(p + 4)^2 ≥ 18 take the positive root
p + 4 ≥ sqrt (18)
p ≥ sqrt (18) - 4 ≈ .2426 = the smallest approx. + value of p that will give real roots